I don't use a Surge but when the Nuke came out it had very similar. characteristics and I was telling people it was a faster Surge.
I would feel both of them out and go with the one that feels the best.
I actually got an esp Nuke but wasn't that impressed. I have gotten pretty comfortable with what I have and I know them well, but I still get excited about shiny new plastic when I'm looking at discs.