If you have experience working on bikes and you have all the specialized tools, access to the tools, or are willing and able to buy them, why not?

If you are naive to bike mechanics, one thing to consider, which I wish I had thought of early in my wrenching career: when you are new at it, regardless of how carefully you read sheldonbrown.com and how careful you are to use the right tools, you will soon ruin at least a small number of erstwhile valuable and functional components and tools. And you'll say to yourself (especially later, after you've realized just how nice those components were before you stripped their threads or broke them in half): Why didn't I start with a rusty Schwinn Varsity?

If you don't have bike mechanics experience, we usually recommend the Schwinn Varsity to start. No special bike tools necessary. Pretty much all nuts and bolts.

So say the pros.

Amen.