Seriousy Ralph, what pistol do you have? There is quite a difference in the Glock, Browning or Baretta holsters.
The best stuff comes from the States
I managed to get a really versatile holster that tucks away on my body armour, and out of the way of the straps. Works a treat for me, but might be wrong for you. I got it from
OPSGEAR
Here is a link
Blackhawk Universal Spec-Ops Pistol Harness
However I have got on really well with a very cheap velcro pistol attachment that sticks like glue and comes everywhere with me. It seems to work best on my body armour on the chest. This gets my best rating You are only limited with your imagination by this one you can wear your pistol wherever you can put velcro. (no duff, seen someone use it as a NVG counter weight)
Universal Holster with Hook & Loop
If you want something closer to home Give Wolf Armouries a call: Tel : 0870 754 9653 or 0207 284 0001 They are based in Camden, and have the largest selection in the uk. They can talk you through the options and let you try before you buy. I thought they were just dealing in replica stuff, but there are some great holsters.
To be honest I think leg holsters are just for posers and yanks. They are a pain in the arse, and are bound to snag when you need to get out in a hurry. You might as well put it in your leg pocket for the same effect.
My wife stole my holster when she developed a fear of pedaloes!