I'm extremely picky when it comes to anti-perspirants and deodorants. I want something that will be easy to apply, that won't stain my clothes and obviously protect me from odor and sweat. The great thing about roll ons versus stick deodorants is that they don't feel waxy and do not leave a ring on your armpits. I always had issue washing away the deodorant stains on my shirts- even if it's a clear formula, there is always some residue that's hard to remove due to its "waterproofing" qualities. Dry Idea goes on wet, but dries quite quickly and leaves a very light, powdery residue at the end of the day. I use the unscented variety which is great if you're senstive to fragrance or don't want your deodorant to interfere with the smell of your perfumes or lotions.
It's the only brand I use for the past 5 or so year and it's great.

I can't remember how long I've been using this anti-perspirant. It works great, and I've never had a reason to stray away from it. It doesn't stain my clothes - with the exception of one white T-shirt, which is a little stained, but I'll let it slide because it hasn't stained anything else!