I wore a galco for years with my J frame - if you drive a bunch then it's very easy to draw while seated. I would go with hammerless for revolvers as the exposed hammers will wear holes in your leg or pants over time, also this is the most likely item to snag on a draw. Just make sure any holster you buy has really good padding and retention, very embarrassing to be walking down a stair well and kick the gun out with your other foot. I prefer Velcro wide strap vs buckles and snaps, you can put it on tight but not cut off the circulation in your leg. Also it may take sometime to get used to the weight of the gun as you walk, but if the holster is a good fit you will become use to it and not limp or walk funny.
As for lint and dirt, yes you will collect some but my J frame would always fire even if I had not cleaned it for 8 months of daily wear (yes, I know you should clean it more often, but when you carry everyday for work it tends to be overlooked).
I also tried the ankle holsters than had a calf strap that is supported to take some of the weight off your ankle, was not a big fan as now I have two areas on my leg in contact with a tight hot strap.
