I soldered water pipes for the first time last weekend. I thought it
was easy enough to do, but I have had lots of experience with
electrical soldering so that helped. I didn't even bother practicing
first. The hardest part was that afer I adjusted the flame I had to
deal with gusts of wind coming in through a crawl space and changing
the size of my flame on me. I can say that if you have a lot of
patience and prep everything properly, use enough flux, and heat up
the pipes enough, then it should work. I had some vertical pipes with
water in them that I drained by sticking a straw in them and sucking
out the water as far as I could and that was enough to make it easy to
solder.