I've not played a Telltales game before, but watched a few, so I knew pretty much what I was getting into. Oh, and I put a few hundred hours into Borderlands 2 as well. Eep.
In general, Tales has good characters (a couple I really liked quite a lot), the plot is ridiculous but that's what you get from Borderlands (space in particular is remarkably forgiving), and the dialogue choices are generally fun. There's some good humour in there, and it's not quite as puerile as BL tends to get (thankfully). Some fairly big name characters are in it, and there are a couple of cameos as well. I guess the very finale is a bit of a whimper, but it's pretty expected really. ~2 hrs per episode, so about 10 hrs all up.
I'd recommend it if you're into Borderlands at all and don't mind something a lot less actiony. Probably doesn't do much for non-BL aficionados though.