I have this lens and overall i'm impressed. With a 450mm (35mm equivalent) reach it's not great for small wildlife unless you're really close, but there are some great examples on here... I'll try and dig some of mine out later when I hook my ext drive up.
A few have reported that the lens goes a bit "soft" from around the 280mm mark. This really gets on my nerves, but then others have posted some very good photos at the 300mm mark.
The VR works very well on this lens and is instantly noticable through the viewfinder. Focusing is quite quick and very quiet. I've tracked seaguls in flight with this lens with some good results.
I'm in a similar position in that fass glass is out of my reach at the moment, and the 70-300 is 5.6 at 300mm, which isn't great, but in good light it works well.
You may want to try one in your local camera shop first, to make sure you're happy with the focal length.
I'd say that for the price, you would struggle to get a better lens.
If your only shooting wildlife on a adhoc basis, you could consider hiring a longer/faster lens... that's something I'm considering (as well as the Sigma 150-500 OS, around £700...!)
All in all, it's certainly not a bad lens, and I'm sure others will say the same, do a search on here and I'm sure you'll get some examples...
Hope this helps