The 94 epi i tried had a maple neck at least, mahagony will have a brown to reddish brown color. Youll be able to tell the difference immediately if you have a look at your gibson. And anyway a good epi would defintely sound better then a bad gibson, so i wouldnt worry too much about it.
Mahagony is supposed to sound a bit dark but still quite clear(highs, if even denser, sparcle), didnt find the lighter(in weight not color) asian grown mahagony had these characteristics, and just sounded dark to me. Probably there are some nice samples though, never cared to find out.
Anyway, i thought the epi sounded OK for the price, but i didnt like the feel of it.
If you like playing it compared to your Gibby, i would surely keep it, you cant have enough guitars IMO. With me it would end up in the back corner for sure..... :P
Im sure a basswood guitar can sound better then any of my gibsons by the way, but a quality guitar is not all about how it sounds, its a variety of aspects. Its like with cars, there is more to them then how well it drives.......
Anyway, nuf said, as long as you enjoy it, keep it. If you dont use it anymore, toss it. At least thats how i think about it.