Overall, I find Ska to be pretty lousy.
There are very, very, very few Ska bands I can get behind. I find stuff like Reel Big Fish, Save Ferris, and other bands like that are pretty generic and boring. My biggest issue with it is that most Ska bands don't focus on developing musically and just rely on the horn gimmick. Streetlight Manifesto isn't really Ska as much as it is a punk band with horns, especially with their recent albums there isn't much Ska in there other than horns. I find Streetlight pretty boring anyways, all tunes are the same and far too long. Kalnoky is a good guy though. Then you have stuff like Pepper, Sublime, etc, which is essentially just boring bro-core reggae. From what I've seen, a lot of people really get into Ska for a short period of time during high school and burn out rather quickly because most the bands are essentially the same.
I won't even go to Ska shows anymore because the crowds are full of annoying 14 year old kids, not to paint all Ska fans with one brush of course, but that whole 'Skanking' shit needs to stop.
However, I like Big D and the Kid's Table, even the more recent album. We Are The Union is also pretty good, decent mix of pop punk, ska, and thrash. Bomb The Music Industry! is likely the best band with Ska ties around, but they can't be put into any one genre. There are a small handful of bands that are pushing the boundaries of the genre, and I can get into that. Other than that, I couldn't care less about Ska.
BTMI:
WATU:
Big D:
Also, Operation Ivy is classic.