I have had the AFS 70-300 VR for a year now. Between 70-200 it is as sharp as you need for 8x10 sports pictures. I use it exclusively for youth football and baseball (all daylight). I crop every photo, and it's still great. It is not quite sharp enough at 300mm wide open, if you need to crop and enlarge a lot (like for outfield shots in baseball). I'm looking to perhaps get the 80-400 VR or a prime 300 f4 for that purpose. Colors are great. Even if I upgrade for baseball, I'll still use the 70-300 VR for football.
I also have the 70-300 ED, which I bought in 2001. I took some great sunsets, as well as sport shots, with that lens. It is also a good lens, but I think the VR version is a little better in just about every way. Slightly sharper, slightly more contrast, much better AF. The ED is a little smaller, and noticably lighter, as well. Truth be told, it's also just fine between 70-200. The only reason I upgraded was to get AFS, which makes a big difference, especially in baseball.