Neither, save your money and wait to buy higher quality cymbals. I was thinking about going either the ZXTs or ZBTs a little while ago, but found neither were worth it.
I suggest the
Zildjian ZHT series or the
Sabian Pro Sonix series. Both are 1 series higher than the ZXTs or the B8 pros. Or even, save for even longer and go for even higher quality, buying the cymbals one at a time. Also, I would say don't feel restricted to brand or series, just buy what sounds good to your ears.
But, if you really must have new cymbals or are really desperate, I would go with the
Sabian cymbals, I prefered their sound when I had heard them.
Hope that helped in some way.