Skimmer advice please

[patpare]

Well today I'm looking to order a new protein skimmer but due to all the option out there I'm kinda flustered on which one to get.
I need to make the best choice as possible cause I don't get spare cash to often to make such a big purchase. I've been using my SWC 120 cone skimmer for 7+yrs now and it's still works like a champ. But like I said spare money doesn't come around to often here,so knowing that skimmers are essential to successfully keep sps dominant tank.

My tank is a 30g +another 15g in my sump.

So my choices are

Coralbox D500
Bubble Magnus Curve7
Vertex omega 180i

Thank you
Pat