Ever used a plasma cutter? Once you do, you'll try to use it on everything. Gotta have a good air supply too. As for the welding point, my thoughts have always been buy the best welder you can to get the strongest and best welds you can, especially if you're welding any structural parts.
I actually just bought one a few weeks ago and used it one time. Went out to use it the next day and the pilot arc wouldn't work so I boxed it up and sent it back. Im gonna buy another one after Christmas im broke right now!