If your going to use copper I would recomend getting a TS4000 torch. Its a trigger start torch that lights every time. Use propane or MAPP gas, mapp is better for fittings 3/4 inch and up. It gets the joint up to temperature before you burn all the flux out of the joint. No electric cord to wrap yourself in and fire is out when you don't need it.
PEX is some good stuff but expensive for a small job. One thing to consider with PEX is you can have far less joints than copper. Copper seems there is always one joint in a hard to reach location that leaks.