I'm 5'10" and 200. The low profile seat from newspeedmaster fit me just fine. I spent quite a few 200-300 miles days on that seat without any problems. Doing more than that wouldn't have been a problem. It's already been said, but it allows you to sit down in the bike more, and it really helps you "feel" the bike better.
Dog is right about the gel pads helping with comfort. It's a low cost alternative to a custm touring seat, but if you are looking at the low profile seat you probably like the style of the seat and adding a gel pad to the stock seat just doesn't have the same look.
If you like the looks of the low profile go ahead and buy it. It's a great seat.
