I have two random orbital sanders; a 5" Porter Cable variable speed and a 6" Dewalt variable speed. They both use the hook and look fastening system which allows reuse of pads (assuming they aren't worn out). I have had absolutely no problems with swirl marks and would never consider going back to the older style sander. (I actually gave mine away.)

The Dewalt is a right angle style and is wonderful for removing large amounts of material or working on wide surfaces. Likewise, the 5" Porter Cable can get into smaller nooks and crannies. I was able to hook the exhaust of each into a shop vac system which GREATLY reduced the dust levels.

The only "downside" is that Home Depot in my area (Dallas) seems to have stopped selling the 6" hook and loop sandpaper. (It is available through most mail order tool catalogs and Lowe's in this area still carries it as well.) The 5" seems to be slightly more available.

I would highly recommend that you consider the few extra dollars and get a variable speed model. It really allows you to fine tune your rate of material removal.