I am looking for a system to put into my Twin Hammers. I already have a Tekin RS and would like to go with a Pro4 3300. Will the RS be able to handle this? If not, how about a MMP?

YES to both.

I wouldn't. I tried an rs pro with a castle 1410 in my hyper tt and it really wasn't happy.

Directly from Tekin:

http://www.rctech.net/forum/10219196-post5.html

The MMP will handle it or get an RX8

I ran both ESC's listed with a Ubec and had no issues in anyway..

Not sure how the UBEC factors into the equation. The motor will pull more amps than the esc is rated for. I think TY from Tekin knows what he is talking about and from my experience it didn't work well.

However if you like smoking esc's then by all means go with an RS and a 4pole.

To reiterate, the MMP or the RX8 would be fine (I use an RX8/4600 in my SCTE and a MMP/1410 in my Hyper TT)

Go with the Roc412 series of motors. That's what they're meant for