Whichever you decide to go with, definitely go for some test rides if you can. I had my heart set on a Giant and after a few test runs on one decided they weren't a good fit for me.
As far as XC vs Trail... I stuck with trail knowing that I was getting a ride that would let me hit the biggest variety of terrain where I can ride most often and I'm simply not good enough (or light enough, if I'm honest) to justify shaving ounces or travel off a ride so I can climb just a tiny bit more quickly.
But if you can tell a difference... that's all that matters—smiles on every descent!