So I've had my SG for about 6 months now and I've only had to change the strings about 3 times. When I bought it the guys at guitar center gave me these DR Tite-Fits (Nickel Plated, Round Core) strings, and that got me thinking. What difference do strings make, and do you have any suggestions for an SG? I heard Ernie Ball's were good, but I've never really noticed the difference that different strings make

The kind of string you use determines how bright your sound can be. For an SG, i would use DR's or Ernie Balls.
I love Ernie Balls to be honest. My friend ussed elixer nanowebs religiously until i got him to try the EBs. use those man and see how you like them
I know it gets pricey, but I always say you should try out your options for strings. You never know what will sound best or which ones you'll like the most until you go through them. I do like ernie balls on my fenders but I use DR's on my danelectros. It's a preference thing though.
Cool, thans a lot I think I'm going to try the Slinky's out next time I'm at guitar center