Neji is the one at a serious disatvantage. Who cares if he has a blood limit. It isn't like Gaara's demon is exactly the hot new trend out there. So he can dispel chakra? Who cares. If you looked at my last post, it wouldn't matter whether or not Neji can dispel chakra against sand.
Neji is a close combat fighter in which his techniques either involve him standing still or have that chakra induced techniques come at him, while Gaara is mostly ranged. While neji is chillin on the ground, Gaara could simply move a mile away or float in the sky far out of reach. Then just make a mountain sized worth of sand lump and drop it on Neji's head. He could dispel all he wants, but he isn't going to survive that kind of force.
The fact remains that Gaara is practically earth itself. Neji can't fly, so how hard would it really be to make traps in the ground that Neji can't counter, or wear him out. We have seen how he dealt with Orochimaru's spider bodyguard, and he barely stood a chance then.