Really?! Im not going to blow a hundred bucks on a whole batch of a single board that may or may not work and then have to go through the hassle of liquidating all the ones I dont use. Look, its your preference.
If Ive got 2 or 3 weeks to play with I would rather spend the 30 minutes some evening to whip up a little board for something in Eagle, zip it over to sparkfun, and when it comes back, happily put together a nice professional board in just a few minutes. The alternative is hassling with perf boards, making all the jumper wires (Ive always hated stripping wire... ::)), and then spending the rest of the afternoon troubleshooting some errant solder bridge. Plus, Ive always felt anything Ive ever put on a perf board just seems so kludged together and altogether uncool.
When I consider what my time is worth, and the fact that I have very little of it, it makes sense to effectively have someone else do it. $25 + an hour or two work for some standalone board is a bargain compared to what, maybe a day or two's worth of work? What do you charge by the hour?
Anyway, the added benefit is that whatever I do in Eagle is repeatable, if I, or someone else, find themselves needing a similar solution to one that Ive already drawn up. This way I use sparkfun as a cheaper prototype and then I take the design to Gold Phoenix when I need a larger batch done. Id rather spend little and wait awhile just to know the design works before having a 100sq in coaster.
But honestly, YMMV. Just saying that for anything smaller than about 5"x7" batchpcb makes a lot of sense and is in fact a good alternative for final, professional designs.
Cheers,
Brian