fwif, i just finished repiping my whole house. first time i ever did any sort of plumbing with copper, 1/2" and 3/4". turned out great, as inspected by a buddy of mine who works as a pipefitter. not much difference, i think, between 1/2 and 3/4. but get mapp gas, not propane. and practice a little. plenty of demo videos and advice here and elsewhere online.