I have a bike that I bought at the shop and a bike that I built myself. The shop-bought bike gets free tuneups for life, so I like that. The one I built gets free tuneups for life, but I don't get the chance to go into a shop.
If you have the time and patience, working on your own bike is not only a great money saver, but a great way to get to know your machine and very cathartic as well. I went from not knowing how to set up a derailleur to "Hmm, the downshifts are a little sluggish," *quarter turn of barrel adjuster* "Yeah, that's better."