I usually never second guess myself making big purchases. Hell, I didn't second guess my house, my last car I bought, etc.
For some reason, I'm second guessing myself here. I got a great deal on this TV (IMO) for $1899 in my opinion, but two things are eating at me:
1) I could've gotten the 550 for $1299. $600 is a lot of money for the same size TV. Are the features that the 750 offer worth $600 more?
2) With this model coming out a year ago and the B line out now, in a year from now, is my TV going to be completely inferior (i.e a "C" line for example)