I like Universal Clays in the .40. It works well with 155 to 180 Gr bullets, at least the jacketed and plated I have tried with it, from light loads to max loads. Unique is similar in burn rate so I don't see why it would not work well too. Unique has a great rep for accuracy, as well as not being the cleanest out there. Not filthy, just not the cleanest.
I like 180 Gr bullets at 850 ish FPS for plinking in my 3" XD SC. Even 950 to 1000 FPS is much better than the snappy high speed 155 Gr loads. Very pleasant. 155 gr bullets at 900 ish FPS are pleasant as well, even out of the light 3" XD SC. Of course, those loads clock a bit more from 4 or 5" guns.
I suspect Power Pistol will be a bit dirty loading light plinker loads in the .40, but they will work. It should excel at pushing it hard. It should shine in the 10 MM I would think, but I have never loaded 10MM. Maybe someday.