the return pipe will have to go over the back wall. unless you want to drill a hole for return piping. i would just go over the back. it gives you more flexability and the ability to move it down the road.
as for the overflow, i have looked at it, and it is really loud on the videos. plus i really dont like the design. thats not to say it wont work.
where is the tank going? if in the living room, the it will be loud. if you have a fishroom behind the tank, it might not be as big of a deal.
give us some more information.