Having used quite a variety of different programs for pixeling (though still not getting all that great at it) I've come to the conclusion that my least favorite two programs for the job are mspaint and photoshop. I dislike photoshop merely as a matter of preference, but mspaint is ultimately inefficient, and generally, it seems that people who use it and harp on it are either too lazy to get something else, or simply don't want to, because that would mean having to "learn a new program"...which equates to laziness in my book.
I mean if you *really* feel the need to keep using a program that's restricting you for no good reason, be my guest. just let me know how much fun you're having with your three levels of undo and no layering ability. and that god awful curved line tool.
Since i primarily deal with animating, Graphicsgale handles most of my present needs. however, i'm not under the assumption that it's the best thing out there, it's just what i use 'till i find something better. it took a bit of getting used to but trying to use mspaint now... just doesn't work too well. Put it this way. Before i got GG, i was using mspain (not a typo) and unfreez. and irfanview to convert the images since mspaint's gif compression looks like pure ass. and not a good, curvy round ass; a cellulite shocked overblown old lady ass.
I'm not going to bother posting examples because that mess should explain itself; but in terms of sheer output it'd take roughly the same amount of time for me to produce an 8 frame animation using the old method, and using GG ALone, in he same timespan i can churn out 30+ frames. it sounds like an exaggeration ,but it's really not.