X-heads or J-heads on a 360 LA Engine

I have a 360 engine and a set of J-heads (3418915 castings). The heads are the 1.88 intake valve version and supposedly have combustion chambers that are somewhere between 65cc to 73cc volume. I haven't measured them yet. I have an opportunity to pick up a set of X-heads (2531894 castings). I don't know the stock combustion chamber volumes for these heads but they have 2.02 intake valves.

My question is, would the X-heads be a better choice for the 360 LA build? I was planning on flat top pistons and would like to settle around a 9.5 compression ratio. Should I pick up the X-heads or just stick with the J-heads. They're basically the same casting as I understand it.

Thanks for your thoughts.