I envy you!
Well if money is no issues then hehe http://mr4000.com
... hehe. In my opinion it cost way to much for the actual viewing area in the end.
The general rule of thumb is bigger is better for a simple reason. If you loose a gallon of water on a 29 gallon from heat then the salinity change will be much more then if you loose 1 gallon on a 150 gallon tank? see the logic. Also there more "forgiving" to overfeeding etc etc.
With that said I would think too big is a bad thing if your not capable of keeping up with a huge tank then no need for one. Water changes can be difficult and time consuming taking care of the tank also can be.
I started with a 10 gallon went to a 15 then to a 29 then back to a 15. The reason I went down was money I did not have money for lighting for the 29 but I did for the 15.
I would check the paper.. I think Most of us here consider a larger tank to be over 55. That seems to be the ideal starter tank for the newbie. But by all means if you can go bigger then by all means go bigger. but be prepared for the price grows quite rapidly.
good luck and welcome to the saltwater world