6.1 heads are all the same, they flow a little better on an early 5.7 and will give a little compression bump and a compression drop on the 2009 later 5.7 They flow about the same as a later 5.7 head so not an upgrade unless you need to drop the compresison for forced induction .

If your upgrading an early 5.7 than the later 5.7 head is a great upgrade, you get the best flow on that bore size of any un-ported head and you get almost 12 to 1 compression witch is still pump premium friendly unless you have a bad tune.