Finally gone out and bought a drop-leg holster, just for research purposes.
It's pretty good quality for the $13 price tag. Just fits a Maverick. Will take a Spectre, Wipeout and NF fairly easily, but a barricade doesn't quite fit. With a bit of hook and loop velcro though, it would fit rather well. Has alot of adjustments to secure your pistol, attaches directly to a belt, with two leg straps. I'm a fairly big guy, and the top leg strap just fits, so should be suitable for most people. Only one colour, but what more can you ask for the price? The material and stitching seem to be rather good, but field-testing is something that I haven't tried yet.
Available from Deal Extreme: