It's hard to explain, really.
All I can say is go into each one and mess around to see what you're most comfortable with.
Oekaki BBS will give you infinate layers and is somewhat more user friendly for people new to oekaki. But it has been known to error and flip out on some users. Plus if you accidently back out of the window that Oekaki BBS is loaded in; it's gone forever. It's not good times. :(
Paint BBS will only supply two layers and it's not very user friendly for new people to oekaki. IT's one of those things you need to poke and prod around for a while to get the swing of things. Paint BBS has a more advance selection of tones, and.. stuff.. hell, I think the tones are the only reason some people like it better. For me: I like Paint BBs better for the fact I can do more with it than Oekaki BBS. Coloring my lines, image recovery for those "oops" moments, and more stable layers. Well, yeah, you only get two.. but if you're skilled enough in zee Paint BBS, you can get around it with ease (Whoring the unify layer tool ftw). Plus the fact Oekaki BBS layers tend to goof up when submitting the finished product. And fixing it is sometimes impossible.. It CAN be done if you're lucky enough.
Shi Painter.. I don't know, really. I've never messed with it. I suppose you could ask Cho about that.
Don't take my word for it.. I'm overly biased towards Paint BBS. I'd suggest asking other people about them to get the whole story on it. Or you can, you know, look for yourself! And fuck you for making me type all that out. I had originally planed on just saying "Look yourself" but I got carried away. Ass. :( <p><div style="text-align:center">
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