I guess I don't understand what all the fuss is about?
I'd just buy a cordless metal saw and be done with it. One tool required. No hacksaw, clamp, or tripod required. Lay the pipe over your leg, ladder, etc and zip through it. You'll be done cutting it before you'd even get the clamp tool on it and hacksaw out. I've never had a problem with unsquare cuts either. So far my Dewalt blade has lasted 1.5 years, quite a bit longer than the sawzall blades I was using before.
FYI, I would not recommend the metal blade in the wood circular saw. Safety glasses can't even save you from those chips, they go EVERYWHERE!
This thread reminds me, I need to have a bracket built for my bumper to hold a rigid pipe vise. I'm tired of packing a tripod to thread a few pieces of pipe.