I also think the FIST #1 is a good holster. I have one for my SP-101 and my 642.
I am positive it is not the very best holster for keeping everything in place tightly, but I cannot think of a more versatile and easy-to-use holster.
With this simple clip IWB holster, I can carry IWB strongside, IWB cross-draw, and between the belt and pants in either position. I takes only a few seconds to put on or take off, and it even works without a belt IWB.
They're also well-made, and the retention is strong for an open holster. I've carried for a year and a half without having to purchase a real gun belt.
To be fair, I'm still going to get a real gun belt, because I think it will improve the performance of this holster.