440 Source Head Opinions?

I've found 440 Source to be one of the very best at customer service. And even though we were never able to get our test ported Stealth heads to flow more than a best of 350 cfm, here is one of their 4.15 stroker kits with Victor heads on the chassis dyno.......


Why would they sell stroker kits and then have stock flowing cylinder heads? They should have an option for a high flowing cylinder head as well