The skimmer looks like a seaclone or similar (crap), but I don't see how you are going to be able to fit a much better one in that sump without cutting some of that euro-bracing away.
, this guy already has this system and realized he needed something bigger/better, so he's selling it. I feel that you are going to be feeling the same way about it in a short time. Someone before me mentioned the front to back dimension- the footprint of a reef tank makes or breaks it.
I would rather have either a 40 breeder, or a 75, as mentioned.