Your assumptions are way off base and since I know Brett very well as he has built 4 engines for me I can tell you first hand that he built a G3 Hemi for a super stock deal and it fought him every step of the way and he considers it the biggest, most expensive POS from any manufacteur.
Okay, my assumption on the reliable power, 750 (n/a) hp is probably high, but it's well proven that boosted they like the LS hold quiet well.
Gen lll heads that flow in the 340 or so can be had ready to run for less than $2K.
The W7, 8 and 9 are proven to work well in the right hands, Brett is the right person. I would like to see what a set of his heads cost though, ready to run. The Gen lll I mentioned Brett building is Dons buddy, he told me last year at Moparty who was building it. The difficulties weren't mentioned. Brett's a sharp guy, if anyone can make one run hard he can.
I love my small blocks but think as more parts are available and folks building them get more stuff figured out they'll be a great engine that's capable of making big power. They already do in boosted applications.
guy he built that motor for is a good buddy of mine. It was a nearly 2 year ordeal. It made 770 ish horsepower, was far from cheap, and my buddy is still having some issues with it. Hopes to put it in the car this coming weekend, hopefully.