My son, Charles, used to occasionally play with a Fort Worth ska band called Cow Sponge, but I'm not sure one would apply the adjective "good" to them. >;^>
I am not completely sure what kind of Ska you are looking for, I am assuming upbeat music with some trumpets and whatnot (brass?), but I would have to recommend the OC Supertones. They have talent musically and have lyrics which are amazing, and seem very Calvinistic (would say reformed... but I don't know everything that entails.)
Musically I do not find their first cd to be that amazing, but the others sure are neat.
I think the W's were ska as well... but they seemed to me to be more CCM and less like something that I would like to listen to. To be fair... I never gave them a chance.
Definitely give the OC Supertones a listen. Even if they are not the Ska you are looking for, they are an excellent addition to any member of the Puritanboard's collection.
My best friend and I would both recommend Five Iron Frenzy - good talent and very interesting music. They are somewhat left-wing Evangelical at times, mostly economics/social justice, but they are pretty good overall I'd say. The Supertones are pretty good too.
For Five Iron, get their last album first - The End is Here, as it will include how they are live and in studio, and give a broad spectrum of their early and later work.
My best friend is a big ska fan and he said in his opinion that about the only genre where the Christian bands are better than the secular ones, which is sad when you think about it.
Oxymoron: (noun) a figure of speech by which a locution produces an incongruous, seemingly self-contradictory effect, as in “cruel kindness” or “to make haste slowly.”