If your intention with the cylinder head swap is to gain +25whp more out of your existing combination, it would be a lot more cost effective to have a custom grind camshaft made for your specific combination. If you pay a professional to grind you a cam, you won't be leaving anything on the table. A custom grinder can maximize the power potential out of all of your parts combined. Off the shelf camshafts perform well because the manufacturer factors in all possible combinations, and if you meet some of the criteria for the combination, you'd expect it to perform as such. But with a custom cam, the grinder will take into consideration YOUR displacement, piston, cylinder head, intake manifold, exhaust size, transmission ratio, rear end ratio, wheel size, ect. The TrickFlow cam seems rather small for a 190cc headed 347 stroker in my opinion. If you factor in the cost of a custom grind cam and all the gaskets you'd need for the swap, you'd probaly be end up spending like $500. That's $20 per whp gained.
The reason I recommend a camshaft swap is because if your cylinder head/bottom end/power adder combination already has the potential to make 500+whp, then the limiting factor is the camshaft. Remember, the cam is what is telling the valves when to open and close, so if you can control those events to suit your combinations needs, you'll make more power.
Also, ProComp and ProMaxx are completely different companies altogether. ProMaxx uses better valvetrain components in their cylinder heads.
