I use Power Pistol for my 9mm competition loads. One of the reasons I like Power Pistol is that is has one of the widest min/max range of most powders I've looked at. I like knowing that I have a greater safety margin should my press throw a high charge. It also tends to have the highest velocity at maximum loads. You can safely go from light target loads to +P loads using the same powder and projectile in most instances.
With the lower level target loads, I don't notice any more recoil, noise, or muzzle flash than 231 or Unique. Once you start getting into the upper range, though, the muzzle flash becomes very noticeable. I would describe it as a bright white jet flame, which was easily visible on an overcast winter day. The muzzle report from the higher loads can be a bit loud too, especially if shooting indoors.
I've heard that the hotter you run it, the cleaner it burns, but I have not had any problems with my light target loads. I push a 124 grain JHP somewhere between 1,000-1,050 fps depending on the pistol, and it's easily one of the most accurate loads I've found for most of my competition pistols.
One of the only drawbacks using Power Pistol, besides muzzle flash & report, is static cling. The static doesn't seem to bother my thrown charge weights, it just leaves a light film of powder coating the inside of the hopper. It's a bit annoying when emptying the hopper, but something I'm willing to live with. I've also heard that the high nitro content can etch or discolor powder hoppers, so it's best to avoid leaving any sitting in the powder measure for extended periods of time.