The best ankle holster Ive found for my 642's, has been the Desantis "Style 44". Its about the only one Ive found that I can wear comfortably all day. I have one for my Glock 26 as well.
Do a search here, or do a google search pf "Renegade ankle holster" Don't know anyone who has one that doesn't love it....and yes, the bottom will look like that after 9 years of continual use...and I plan to get another 9...
I really like the DeSantis Apache ankle rig. It is comfortable enough to carry a heavy gun all day. For IWB I have been using a High Noon Holsters Bare Asset. I am looking into an Offset Holster where the clip is behind the gun to thin out the profile.
I currently use a galco king tuk for my s&w bodyguard .38 spl and taurus m605. the hoslter has a lot of surface area and may get a little hot, but i like it.