One last point - What is the quality of the wire?

Good copper wire is easy to solder. Cheap wire can have a lot of other metals (especially aluminum) that can really dork up your soldering efforts. I recently tried to solder some cheapo jumper cable wires together & actually burned the wire before the solder could adhere.

I don't agree that a butane torch is hard to control when soldering. Unless I'm working in a really tight area, I actually prefer to use one. When in tight areas though, I have a nice butane soldering iron that works really well.

If the wire you are using is a good quality copper, then the solder and flux you can get from the plumbing department at Lowes/Home Depot works quite well. I've always had better luck with flux paste rather than relying on the 'stuff' they have in the core of the solder.