Cast vs. Aluminum heads and bang for buck..

For my own personal motor, shooting for 500-550hp or so, I’d use RPM heads since I can buy them for enough less than TF190’s to make it worth my while to do a little reworking myself.
And it doesn’t add to my cash outlay to have that done.

If I were really trying to be closer to 600..... I’d give the TF’s a try.