I've used the Pro-Comp 460 heads on a 545" solid roller motor I built to run at Bonneville. They need at least 10 hours cleanup time in the ports. They are full of machining overhangs and casting flash. After the prep work, they aren't to bad, but the old addage you get what you pay for applies. If you put them on out of the box, you're wasting your time. If you have to pay a professional to do the work to make hem right, you may as well buy Edelbrocks.
Also, be careful, they use the same funky valve in the 460 heads as their own 351C heads, so the only source for cost effective valves are Pro-Comp or SI. I use bare heads so that I can control the springs used, and the finished product.
A final thought, and this one may affect your decision, they use the standard 460 port location, not the Cobra Jet port. If you want to run a dominator like we did, there are no manifolds that bolt up to the head without massive modification. I used a Performer RPM Air Gap, and welded on a Dominator carburator flange. Then I weded the interior of the manifold under the carburetor and ported/re-machined it to keep it a dual plane. We run a 1050 on it.
It runs well, but rain at Bonneville washed us out in October and rain and wind at El Mirage kept us from running in November, so we won't get to run until May.
2005 F-350 XLT Crew Cab, Long Bed, 4x4, 6.0L Powerstroke, 6-Speed Manual
Projects: 1996 SVT Cobra Blk/Blk, 1970 Ranchero, 429/C-6
I do all my own work. I fabricate my own parts. I build my own engines. I port my own heads. I have my own chassis dyno. I do my own tuning.