In my own opinion, I would not get a shocker, I'v owned both an Ion and a Shocker NXT.
Things I found wrong with a stock shocker (you need to spend however much you buy the shocker for, and then spend that much on upgrades for a feedneck, trigger, board).
The Shocker is supposed to be the best upmarket smart parts marker they make, IMO, save your money and get a planet EGO 06/07, ETEK 2, DM7/8, these will take your game to a much higher level if that is where you want to develop it to be in the not too distant future.
If in doubt try the shocker, if you fall for it get it