I just bought a pair of KRK V4's used on the Sweetwater Trading posts. Must have been used once since the box still had the warranty card and twist tie on the power cables.
I did a lot of review hunting before i picked what i wanted and i am very pleased. They dont go as low as some of the other monitors but i would say they are top dog under $500pr or $250ea. i got 2 for $250 so i am really happy
. My mixes have improved greatly. Before i was doing all my mixing through my Sony MDR 7506 Headphones but didnt care for the sound outside the headphones(truck or stereo). If it sounds good through the KRK V4's then it will sound good on everything else.
I am not a pro by any means and wouldnt even put myself in the middle of the amateur bracket as far as recording goes but my ears are kinda picky and they are in love.
The only downfalls i see with these is maximum volume before clipping could be better and the low end only goes down to 45hz or so. i guess you could add a sub later and take care of that issue but If any one is in the market for some nearfields under $500 I would recommend these.
Mine are located on top of my desk in a less than adequate mixing enviroment(my temporary studio until i build the other less than perfect but much larger than my closet studio).
let me know if ya wanna send some test at them.