Talk about apples and oranges. I think you've got apples and pancakes there.
I've owned T birds, a couple of active Fenders, and an active Squier jazz - which was a freakining awesome bass. Had 2 actually, a 4 and 5.
T bird is deep, dark, heavy, bulky, impossible to put in a gigbag, and has neck dive. It looks cooler IMO than any other bass, and sounds awesome for what it does, but comes with the above pricetag. It's not the most versatile instument on the market, and I would consider it only if I were using it strictly for an original band, or a band where I knew the sound would fit, and I loved that sound.
The jazz bass is a no brainer, you'll be able to do anything with it. Compared to the T bird it's like buying a pair of socks as far as I'm concerned, but it's going to do a lot more, and do it a lot more comfortably than the epi.
Last note on the T-bird - the thing that ultimately made me sell mine was the fact that the case was huge (wouldn't fit in my trunk and barely made the back seat), and I couldn't find a gig bag that would actually protect it. I never use cases, so I naturally I never gigged with the bass. Well, 1 or 2 times, but ultimately it wasn't worth the hassle.