cyrnel

All of these brands (and the no names) resell laptops built by Original Design Manufacturers. The ODM's (Acer, Sager, Quanta, Twinhead, etc) put together new models, shop them around to the resellers (usually with short-term exclusivity), and each brand chooses their own marketing configurations. (HD/RAM/net/...) (Macs are the most customized since it's a different processor platform.) Not to say there isn't a difference in quality, but the difference is between ODMs and not Dell et al, and it changes over time and between lineups. It's tough to buy smart with any recent models because neither side of the arrangement would benefit from you knowing who made what for whom. Best you can do is find a specific model you like and see if you can find the same from a non-"brand" source for a better price.

Edit: Oh, as for Mac vs. wintel, go with what's comfortable. The Mac laptop price premium isn't so bad as with desktops. You'll still pay a bit more for Mac but the interface is nice and its *nix underpinnings are generally more interesting to those with a CS background.