Disagree. Not only are my 205s milled, but my bottom end has the original 86 pistons, which have no notches whatsoever, AND my pistons were .005-.010 above deck. TWs are your best choice for valve clearance if you actually want a head that moves some air. Like anything else though, cam selection plays a big role. My cam has roughly the same valve events @ .050" as an XE 266, and judging by how much clearance I had, I probably could have went even bigger (though a cam with more duration/overlap wouldn't have made sense in my application).
Honestly, I would never spend money on a 165. It is just to small for anything but a 302, your options for growth are seriously limited.
You can have afr 165's cnc'ed, or sell them for good money and trade up, so i see growth is a non issue since they hold their value pretty well (probably better than used heads should).
Do you have any dyno numbers or quarter times with from your setup?
Over the years i have typically been a twisted wedge guy, but as of late it just seems that stock wedges vs stock 165's, the 165's yield better power.
With that said, still one of the best setups i've ever seen was gt40x's with an e cam which ran 116mph at full weight, so....
ty driving, granny shifting. 3300+ race weight with 2.2ish 60 ft. I was having some clutch issues and this year I'm hoping for solid 12s at 110+. See my build thread for info.