You should drive down one weekend and look around. Consider all the pros and cons. Huntsville/Madison County is the largest populated area in North Alabama. If you are use to larger populated areas, you will probably be more comfortable in the Huntsville area. Decatur is within the commuting area, so don't count it out.
Everything you are hearing on this board is true. It is what you need that is important.
I live in Madison and made the decison based up convenience to where I work at the Arsenal. I can leave home and be at my office in 25 minutes, of which 10 minutes is just driving across the Arsenal. I live south of Hwy 72 because of the traffic on that road during the commuting hours. That is what was important to me. Prior to coming here, I lived in Memphis, San Antonio, Atlanta and in Germany. Traffic was a big problem in all cases.
I do not have school age children. I have been told that Huntsville and Madison have some of the best schools in Alabama. You may want to look at this area closely if schools are of the greater importance. This is not to say the schools in other areas are not good.
There are all price ranges of homes available in the area. The further from Hunstville, the better price you will get. With that also comes the commute, cost of gas, wear and tear on the car.
Below is a way to compare taxes between the two states. It may give you a little inside to what you are looking for.
http://www.retirementliving.com/RLstate1.html
Utilities are relatively low (Huntsville Electric), North Alabama Gas, Madison Water. We have not been forced into any cutbacks other than voluntary during the recent drought. No where near as bad as the Atlanta area.
Welcome to the Huntsville area and I think you will be pleasantly surprised.