Last week I was one of the lucky few to get one of the government rebates (Texas edition) for a new water heater. The program allows for a $190 rebate for a model with an EF of 0.62+ and $255 for a model with an EF of 0.67+. Today I had a plumber come out to give me an estimate and he informed me that to qualify for the $190 rebate, I was looking at spending at least $400 more than I would for a unit that didn't qualify. I was only requesting a quote for Bradford White models (he said that's all he wanted to sell me anyway).
I know prices vary by location, but does the extra $400 estimate seem reasonable? I would also consider Rheem. Would the same thing be true for their units as well? This is for a gas water heater.
We are looking to buy a new house, so I'm not willing to spend an extra ~$200 for someone else to get the benefit from.

I don't have any problems with the State water heater that I have now. It is 17 years old and located in a closet in the middle of house and doesn't have a drain, which makes me a bit nervous. It does make a popping noise after we use a lot of hot water but the plumber said it was harmless (something about the sediment in the bottom popping as it gets heated).

Thanks for the advice,
Jeff