The one you are looking at in the ebay link Flatbaroque, has "Bubinga" back and sides, not Maple! As for the bridge, I don`t see a crack, it looks fine to me.
I own a 1994 J-100 Xtra with Mahogany back and sides, which is a fabulous guitar, warm and punchy with that great Gibson woody tone. A year ago I tried out a "Bubinga" version, and that was everything my guitar was, plus a bit more. It had a bit more depth, warmth, and a little more zing to the trebles that mine didn`t have, if I had had the funds at the time, that would have been coming home.
I am not a great lover of Maple backed guitars in general, but all the J-100 Xtras I have tried have been excellent, including the Maple, but particularly the Mahogany and Bubinga versions. They are built with the same bracing as the J-200, they are the same size as well, the only difference is the lack of bling, and lets face it wood has a much better tone than MOP or pearloid!
The J-100 Model is a very underrated guitar in my opinion!
Steve.