I've used a bunch of Blue Dot in the past. It's relatively clean at 9mm pressures, and fills the cases up nicely - no double charging there. It's always been reliable as far as ignition and performance. And it works well in a wide variety of higher power handgun and magnum handgun applications. Makes nice fireballs at dusk, too.
I'm thinking about switching to Clays for a while though, to simplify my powder inventory - hodgdon powders are easy to get around here, but availability of Alliant is hit-and-miss. Clays is supposedly super clean and really versatile, especially for lower-power loads (like in the 38 spl, or for cowboy-level loads). Charge weights are low, too, so you get a lot of loads out of a jug of powder. Titegroup also looks pretty versatile, if you're looking at higher-power applications. But I've always been partial to 'flake' powders - It just seems to me that they're usually cleaner (less coatings needed) and ought to be easier to ignite; although I really can't substantiate that last point. Still, given a choice, I usually default to a flake powder.
I was also using Win 231 but have since switched to Ram Shot Silhouette and have been very impressed. I'm also shooting a CZ Shadow and 1911 in 9mm the 1911 has about 1200 rounds true it and looks amazingly clean compared to the Win 231 after 1000. The 231 seems to leave a lot of carbon in the action and mag well. The shadow I only have about 400 rounds true it but it once again looks much cleaner then when I was using 231.
4.1gr. Titegroup with a 124gr. bullet. Love Titegroup in all pistol calibers I shoot.