I'm not heavily involved in ska circles and I do not know whether they are considered the Good Charlotte of that scene but I sure love Madness. Their earlier stuff is fantastic, and it's the mentioning of Prince Buster that brought this into my head.
I know almost nothing about ska except the names of the famous ska dudes/revivalists. I'm a bad, bad person.
I don't really follow ska, but I have friends that do and all those folks have big respect for Madness, so you've done good. One modern ska band that they have managed to get me into is
The Slackers.
Growing up, I sang until my voice changed and played tuba (sweet) through high school. I've been playing bass for about 12 years (on and off and back on again) now. I was in a band called
Long Distance Runner for three years until they broke up last summer. I'm playing with a couple of them along with the
very dude who turned me on to Achewood in a new band called Wind or Ghost are recording our demo right now, and also in another group that is not named yet.
This is my baby. The company I bought it from,
Carvin makes some very awesome customizable type guitars as well, for a rate often cheaper of an American Fender or Gibson. Basically the instrument,
especially guitar, you choose all depends on the music you want to play. I'm a fan of the beefier sound of the Gibson, particularly the SG, though Les Pauls are pretty rad too. The Jag is certianly a cool looking instrument, gotta go sunburst if that's the route you're looking. I would pay attention to what the players you want to sound like, tonewise, are playing and try to find a consensus. And get rid of the freakin' Crate at the earliest possibility and replace it with some an amp that will let your guitar sound like what it sounds like.
Of course, if you've wanted a Jag for a long time, get the Jag. No law saying you can't get another guitar to go with it down the line...