I have no problems with soldering. Solder joins break when the join was not insulated sufficiently and corroded away, or incorrectly soldered i.e. too much solder in the join. i don't solder too often as i try to make everything into neat harnesses that can be unplugged if you have to remove anything later down the track. I have my little narva connector box that i use for all my jobs: http://www.narva.com.au/Terminals_9.html part number 56250. The kit costs under $80 and all you need to get is a decent set of non insulated terminal crimpers which cost around $20 at dick smith