Finish school first, if that's where you are. If its post-secondary, it'll help in the long run and the reserves will give you money on top of your salary to cover tuition and books. The $20,000 signing bonus is nice, but I wouldn't use the reserves as my full time job just to get it. You'd end up losing more money by working those part-time days and having no benefits then just heading straight into the Regular Force.
There are a few of us operators floating on the boards, a lot of varied experience as the trade can have diverse postings and taskings. Throw some PMs around and find out if its right for you.