Lots of previous threads on this if you do a search. Basically, no, it's not a Gibson in terms of quality, but pound for pound they're great basses, and I'm yet to come across a bad one.
I had a white one to use in a classic rock band, expecting to have to upgrade it I was shocked to realize it didn't need upgrading at all. The pickups are beefy, the neck was really nice, and as long as you can live with the neck dive, with an Epiphone Thunderbird, you've got a brilliant bass.
I'd always hesitate to tell someone to get a bass without trying it first, but a TB is as good a punt as any if that's what you're going to do.
Some will argue the Tokai glued neck versions are better, I personally don't think there's much difference.
Epi TBs are great basses.