WoW!!! Thanks for all the reply's.
The reason for choosing between these two tanks and not a larger one is the lack of funds.$$$$$$$
I just sold my 135g tank. So with that money, I not only have to purchase the tank, but everything that goes with it.
I will build my own stand, and I have 2 Emperor 400's to get it started once it's set-up. That's it.
So the rest of the filtration,substrate,plants/decor,lighting,heating......
Whew!!!! My fish need to get a JOB!!
But anyway, the 8x2x2 will cost me $625.00 Tank only
The 6x2x2.5 will run $695.00 Tank only.
The next step up is a 300g which is a 8x2x2.5 $895.00 Tank only.
Thats almost a $300.00 increase for 60g of extra swimming space.
I can purchase a lot of stuff for the 240g with $300.00