Windows shell replacements

Haven't found similar thread, maybe that has been discussed before, however:

Does anyone use Windows shell replacements, such as Aston, Blackbox, Litestep etc...

I even don't remeber how long ago i stopped using explorer.exe as a shell.

I've tried a lot of them, for some time was stick to Astonshell, (www.astonshell.com), but for last two years i'm using bblean (http://bb4win.sourceforge.net/bblean/), lovin' it very much because it's very stable, customizable (tons of plug-ins) and very light on system resources (takes only 1.5 - 2 Mb in RAM).

By the way, does using shell replacement affect overall system security somehow? I guess it does, because it is not so popular as explorer.exe and not so interesting for hackers as an object for research of vulnerabilities.