I figure it can't hurt. The way I see it, a scammer isn't going to go through the trouble of creating an entire E-commerce site, so that's not a worry. If the store really sucks, and you don't get the right product, or whatever, and they don't work with you on a return, then you just dispute the CC charges.
lastly, I actually prefer dealing with the lesser-knowns. I find that the smaller the company, the more each individual sales means to them, and so thier staff tends to be a lot more helpful, and they'll really try and keep you happy. When I dealt with TankGuys, I had a quick question about if a hard drive was compatible with the DVR I was upgrading. They sales guy sent me back a page long e-mail, detailing why it was compatible, and other alternatives I could use (that were cheaper even), and then he also included a link to another webpage with great instructions on how to do the upgrade. How many other stores would go to that trouble?
lastly, a year or so ago I bought a piece of memory from Monarchcomputer, and they were also really helpful with a compatibility question I had. The shipping was prompt and they were just generally helpful with the whole thing. Although, I still don't like the site or thier higher prices, but I suppose the high price does bring a decent service aspect with it.