Soon to be released is the Taurus PT 809b (9mm) with other possible calibers coming (845, 840..?.). It is is like a compact 24/7 OSS from what I have seen. The Taurus 24/7 is really very comfortable for CCW, but then again I have no problem toting a PT1911 or PT92 either. Small of the back when walking or often in a shoulder rig. Shoulder rig is very nice for vehicle trips.
I know it would void a warranty, but I toyed with the idea of cutting off a portion of my 24/7 lower grip and using PT145 mags. Dropping 2 rounds from the mag would be around an inch plus in grip length for a 45cal.. If you don't mind all metal, there is PT945, PT909/PT908 (9mm), PT917c (shorter version of the PT92, with 20rd mag in 9mm) too.