overflow ???

[Just2Bad]

Hi, I'm about to order my new tank a 90G. I need to know how I should built my overflow.. Wich one of these is the best or maybe another suggestion... My bulkhead would be 1 1/2" but I need to decide how big I want my overflow so please give me some advice. I have to give my choice tomorrow morning...

Where I'm ordering it, the guy had suggested me 16", I think at 16" I'm loosing too much space ????

Thanks