diff --git a/main.c b/main.c
index 992aede..5af11c6 100644
--- a/main.c
+++ b/main.c
@@ -46,7 +46,7 @@ static void usage(void)
 	print_output("     -g            gzip compression using zlib\n");
 	print_output("     -z            zpaq compression (best, extreme compression, extremely slow)\n");
 	print_output("     -M            Maximum window (all available ram)\n");
-	print_output("     -U            Use unlimited window size beyond ramsize (100x slower)\n");
+	print_output("     -U            Use unlimited window size beyond ramsize (potentially much slower)\n");
 	print_output("     -T value      Compression threshold with LZO test. (0 (nil) - 10 (high), default 1)\n");
 	print_output("     -N value      Set nice value to value (default 19)\n");
 	print_output("     -v[v]         Increase verbosity\n");
diff --git a/man/lrzip.1 b/man/lrzip.1
index 5bbf8ed..75348c9 100644
--- a/man/lrzip.1
+++ b/man/lrzip.1
@@ -48,7 +48,7 @@ Here is a summary of the options to lrzip\&.
   \-g            gzip compression using zlib
   \-z            zpaq compression (best, extreme compression, extremely slow)
   \-M            Maximum window (all available ram)
-  \-U            Use unlimited window size beyond ramsize (100x slower)
+  \-U            Use unlimited window size beyond ramsize (potentially much slower)
   \-T value      Compression threshold with LZO test. (0 (nil) - 10 (high), default 1)
   \-N value      Set nice value to value (default 19)
   \-v[v]         Increase verbosity