diff --git a/DESCRIPTION b/DESCRIPTION
index 456cdb54..0f27f9cc 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -72,6 +72,7 @@ Remotes:
     cmu-delphi/epidatasets,
     cmu-delphi/epidatr,
     cmu-delphi/epiprocess,
+    cmu-delphi/epidatasets,
     dajmcdon/smoothqr
 Config/testthat/edition: 3
 Encoding: UTF-8
diff --git a/R/arx_forecaster.R b/R/arx_forecaster.R
index c7aebef4..b386fe45 100644
--- a/R/arx_forecaster.R
+++ b/R/arx_forecaster.R
@@ -186,14 +186,26 @@ arx_fcast_epi_workflow <- function(
 
   # --- postprocessor
   f <- frosting() %>% layer_predict() # %>% layer_naomit()
-  if (inherits(trainer, "quantile_reg")) {
+  is_quantile_reg <- inherits(trainer, "quantile_reg") |
+    (inherits(trainer, "rand_forest") & trainer$engine == "grf_quantiles")
+  if (is_quantile_reg) {
     # add all quantile_level to the forecaster and update postprocessor
-    quantile_levels <- sort(compare_quantile_args(
-      args_list$quantile_levels,
-      rlang::eval_tidy(trainer$args$quantile_levels)
-    ))
+    if (inherits(trainer, "quantile_reg")) {
+      quantile_levels <- sort(compare_quantile_args(
+        args_list$quantile_levels,
+        rlang::eval_tidy(trainer$args$quantile_levels),
+        "qr"
+      ))
+      trainer$args$quantile_levels <- rlang::enquo(quantile_levels)
+    } else {
+      quantile_levels <- sort(compare_quantile_args(
+        args_list$quantile_levels,
+        rlang::eval_tidy(trainer$eng_args$quantiles) %||% c(.1, .5, .9),
+        "grf"
+      ))
+      trainer$eng_args$quantiles <- rlang::enquo(quantile_levels)
+    }
     args_list$quantile_levels <- quantile_levels
-    trainer$args$quantile_levels <- rlang::enquo(quantile_levels)
     f <- f %>%
       layer_quantile_distn(quantile_levels = quantile_levels) %>%
       layer_point_from_distn()
@@ -345,9 +357,13 @@ print.arx_fcast <- function(x, ...) {
   NextMethod(name = name, ...)
 }
 
-compare_quantile_args <- function(alist, tlist) {
+compare_quantile_args <- function(alist, tlist, train_method = c("qr", "grf")) {
+  train_method <- rlang::arg_match(train_method)
   default_alist <- eval(formals(arx_args_list)$quantile_levels)
-  default_tlist <- eval(formals(quantile_reg)$quantile_levels)
+  default_tlist <- switch(train_method,
+    "qr" = eval(formals(quantile_reg)$quantile_levels),
+    "grf" = c(.1, .5, .9)
+  )
   if (setequal(alist, default_alist)) {
     if (setequal(tlist, default_tlist)) {
       return(sort(unique(union(alist, tlist))))
diff --git a/R/canned-epipred.R b/R/canned-epipred.R
index 1e088426..8a5baa58 100644
--- a/R/canned-epipred.R
+++ b/R/canned-epipred.R
@@ -77,8 +77,9 @@ print.canned_epipred <- function(x, name, ...) {
   fn_meta <- function() {
     cli::cli_ul()
     cli::cli_li("Geography: {.field {x$metadata$training$geo_type}},")
-    if (!is.null(x$metadata$training$other_keys)) {
-      cli::cli_li("Other keys: {.field {x$metadata$training$other_keys}},")
+    other_keys <- x$metadata$training$other_keys
+    if (!is.null(other_keys) && length(other_keys) > 0L) {
+      cli::cli_li("Other keys: {.field {other_keys}},")
     }
     cli::cli_li("Time type: {.field {x$metadata$training$time_type}},")
     cli::cli_li("Using data up-to-date as of: {.field {format(x$metadata$training$as_of)}}.")
diff --git a/man/step_adjust_latency.Rd b/man/step_adjust_latency.Rd
index 1a677042..0078de10 100644
--- a/man/step_adjust_latency.Rd
+++ b/man/step_adjust_latency.Rd
@@ -267,8 +267,8 @@ while this will not:
 \if{html}{\out{<div class="sourceCode r">}}\preformatted{toy_recipe <- epi_recipe(toy_df) \%>\%
    step_epi_lag(a, lag=0) \%>\%
    step_adjust_latency(a, method = "extend_lags")
-#> Warning: If `method` is "extend_lags" or "locf", then the previous
-#> `step_epi_lag`s won't work with modified data.
+#> Warning: If `method` is "extend_lags" or "locf", then the previous `step_epi_lag`s won't
+#> work with modified data.
 }\if{html}{\out{</div>}}
 
 If you create columns that you then apply lags to (such as
diff --git a/tests/testthat/_snaps/arx_args_list.md b/tests/testthat/_snaps/arx_args_list.md
index 959a5e25..2579c5f0 100644
--- a/tests/testthat/_snaps/arx_args_list.md
+++ b/tests/testthat/_snaps/arx_args_list.md
@@ -124,6 +124,15 @@
 
 # arx forecaster disambiguates quantiles
 
+    Code
+      compare_quantile_args(alist / 10, 1:9 / 10, "grf")
+    Condition
+      Error in `compare_quantile_args()`:
+      ! You have specified different, non-default, quantiles in the trainier and `arx_args` options.
+      i Please only specify quantiles in one location.
+
+---
+
     Code
       compare_quantile_args(alist, tlist)
     Condition
diff --git a/tests/testthat/_snaps/snapshots.md b/tests/testthat/_snaps/snapshots.md
index a03a8dd4..f3e7e573 100644
--- a/tests/testthat/_snaps/snapshots.md
+++ b/tests/testthat/_snaps/snapshots.md
@@ -1093,7 +1093,6 @@
       
       Training data was an <epi_df> with:
       * Geography: state,
-      * Other keys: ,
       * Time type: day,
       * Using data up-to-date as of: 2022-05-31.
       * With the last data available on 2021-12-31
@@ -1117,7 +1116,6 @@
       
       Training data was an <epi_df> with:
       * Geography: state,
-      * Other keys: ,
       * Time type: day,
       * Using data up-to-date as of: 2022-05-31.
       * With the last data available on 2021-12-31
@@ -1142,7 +1140,6 @@
       
       Training data was an <epi_df> with:
       * Geography: state,
-      * Other keys: ,
       * Time type: day,
       * Using data up-to-date as of: 2022-05-31.
       * With the last data available on 2021-12-31
diff --git a/tests/testthat/test-arx_args_list.R b/tests/testthat/test-arx_args_list.R
index 9bbff013..226444e3 100644
--- a/tests/testthat/test-arx_args_list.R
+++ b/tests/testthat/test-arx_args_list.R
@@ -43,6 +43,11 @@ test_that("arx forecaster disambiguates quantiles", {
     compare_quantile_args(alist, tlist),
     sort(c(alist, tlist))
   )
+  expect_snapshot(
+    error = TRUE,
+    compare_quantile_args(alist / 10, 1:9 / 10, "grf")
+  )
+  expect_identical(compare_quantile_args(alist, 1:9 / 10, "grf"), 1:9 / 10)
   alist <- c(.5, alist)
   expect_identical( # tlist is default, should give alist
     compare_quantile_args(alist, tlist),
diff --git a/tests/testthat/test-grf_quantiles.R b/tests/testthat/test-grf_quantiles.R
index e27a0ac6..e2cf90cf 100644
--- a/tests/testthat/test-grf_quantiles.R
+++ b/tests/testthat/test-grf_quantiles.R
@@ -51,12 +51,30 @@ test_that("quantile_rand_forest handles allows setting the trees and mtry", {
   expect_identical(pars$`_num_trees`, manual$`_num_trees`)
 })
 
-test_that("quantile_rand_forest predicts reasonable quantiles", {
+test_that("quantile_rand_forest operates with arx_forecaster", {
   spec <- rand_forest(mode = "regression") %>%
-    set_engine("grf_quantiles", quantiles = c(.2, .5, .8))
-  expect_silent(out <- fit(spec, formula = y ~ x + z, data = tib))
-  # swapping around the probabilities, because somehow this happens in practice,
-  # but I'm not sure how to reproduce
-  out$fit$quantiles.orig <- c(0.5, 0.9, 0.1)
-  expect_no_error(predict(out, tib))
+    set_engine("grf_quantiles", quantiles = c(.1, .2, .5, .8, .9)) # non-default
+  expect_identical(rlang::eval_tidy(spec$eng_args$quantiles), c(.1, .2, .5, .8, .9))
+  tib <- as_epi_df(tibble(time_value = 1:25, geo_value = "ca", value = rnorm(25)))
+  o <- arx_fcast_epi_workflow(tib, "value", trainer = spec)
+  spec2 <- parsnip::extract_spec_parsnip(o)
+  expect_identical(
+    rlang::eval_tidy(spec2$eng_args$quantiles),
+    rlang::eval_tidy(spec$eng_args$quantiles)
+  )
+  spec <- rand_forest(mode = "regression", "grf_quantiles")
+  expect_null(rlang::eval_tidy(spec$eng_args))
+  o <- arx_fcast_epi_workflow(tib, "value", trainer = spec)
+  spec2 <- parsnip::extract_spec_parsnip(o)
+  expect_identical(
+    rlang::eval_tidy(spec2$eng_args$quantiles),
+    c(.05, .1, .5, .9, .95) # merged with arx_args default
+  )
+  df <- epidatasets::counts_subset %>% filter(time_value >= "2021-10-01")
+
+  z <- arx_forecaster(df, "cases", "cases", spec2)
+  expect_identical(
+    nested_quantiles(z$predictions$.pred_distn[1])[[1]]$quantile_levels,
+    c(.05, .1, .5, .9, .95)
+  )
 })