JG....personally I would take a look at the rest of the exhaust system and see what the overall condition of your currently installed system looks like. If some of your pipes are showing corrosion or signs of muffler mender applied to it, you will be better off going with an entire stainless system to keep from nickle and diming yourself along the way.
If the rest of the system looked like it was in good condition, a quick cat and weld would make more sense.
If you go the route of the kit, you should really give it a shot and try to install it yourself. An exhaust kit is one of the easier installs to do and personally feel that $100 for an install is an unreasonable price. A creeper and can of PB Blaster with a wrench or two will be followed by a sense of accomplishment