Instead of ordering by mail, I would check out your nearest Guitar Center just in case you decide you really don't care for them. I can take the same monitors and place them into six different rooms and they would probably sound different in each room. The price doesn't seem too incredibly high on the ones that you listed, but I've heard a lot of pros and cons, mostly cons on this exact monitor. The Rokit design in both the 8" and 6" drivers is just not quite on par with KRK's other siblings. Here again it all depends on what you have now to which you're comparing them to. No two individuals hear exactly the same.
Check out the Gearslutz pro audio forum for more details on these and some other contenders in their price range. I don't like to recommend the monitors I use because of the same explanation as above. I use Yamaha MS10s, Tannoy 8's, JBL and Alesis monitors for close to mid-range applications. My Yamahas are not shown in the pictures, they were replaced with the Tannoy 8 system on the suspended shelves.