What feels good for you?
I use two different ones right now, both from High Noon Holsters;
The High Noon Down Under with straps, with my CZ SP-01 Phantom, and let introduce you to the other half of a good holster system - the belt. That's a High Noon Rock Steady gun belt, and believe you me, that makes a HUGE difference!
The High Noon Double Jeopardy IWB rig, probably the most adjustable rig I have ever used. This one is my wife's shown with her CZ 2075 RAMI BD.
Mine, with one clip set for tuckable, (right), and the other for straight IWB, (left), seven adjustment holes on one side, 6 on the other. This pic was taken the day I got it - it's set up tuckable on both sides. Pistol is CZ P-01.
You asked about single clips - this is the only one I ever tried that worked at all.
Beretta PX4 Storm in a High Noon Down Under IWB. Look at how wide the clip it. Most cheap single clip rigs are far narrower, and...
It's a "C" clip, far superior in both keeping it from rocking and from coming out with the gun. Works well on a real gun belt.
I hope that helped?