I think the issues with the tall tanks are as follows (may not apply to you too much):
1) hard to get good light to the bottom of the tank, especially a problem when trying to grow hard corals (not a problem for what you want to do),
2) hard to set up initially (it is hard to get down in there and do everything you want to do - need to be up higher so you can reach down better, if you plan well and only do your aquascaping once like we discussed, this is not too big of a deal),
3) cleaning - it is a little harder to clean since it is hard to get down to the bottom of the tank...this is somthing you will have to ponder, do you want to have to deal with having difficulty reaching down and cleaning? Part of this is where and how you set it up...if the tank is not too high causing you to have to be on a ladder to clean then it should be ok...think long and hard about where you want to set it up and how you could set it up to make life easier. If you remember...I have a step in front of my tank so I can get in there and work...you could do something similar...
Other than that it sounds like a pretty good deal. Did you like the looks of the tank, does it have any scratches, what kind of powerheads, what kind of lighting is included??
. thats why I come here for advice. Thanks guys. Still lookin for that good deal tank. 
