You'll have to pay the tax regardless if you're registering the car in Texas. The tax is 6.25% in Texas so even if you buy in a state that is say 3%, you'll owe 3.25% more to Texas.
Had my closest one say the same thing to me and then try to sell me one of the ones on the lot xD. I'm just gonna take my chances with one of the dealers already on this site.
This isn't a member only forum, personally I have been lurking here since atleast October reading everything. I just don't feel the need to comment on shit I know nothing about