Reply to Cheap CDJ Question

Ok, my time has come just like many before me. I've been DJ'ing for alittle over a year and a half now, and have been using my S4 for about 8 months now and feel like I should get used to CDJ's. I know I know there are a billion threads about this but search didn't answer my questions so here I am. I want some CDJ's that wont break my bank account but will get me used to the feel of a club setup. I was looking at something like the Gemini CDJ-600 or around those lines to start out with but like I said I just want something that incase the situation comes up where I have to use CDJ's instead of my S4 I wont be fucked. So any suggestions on cheap CDJ's?