VR or not?

I have been photographing birds for about 4 years within the constraints of a fairly tight budget.

About 3 years ago the Nikkor 300 f4 AF-S was recommended to me (to replace my Phoenix 100-400mm lens) and it improved my photography immensely, I love this lens. Over the last few years I have practised my technique and I am getting fairly consistent results in so far as I enjoy the images and I do not have to rely on them to feed my family!

Now I am at the stage where I would like to get some more reach. Rather than struggle with AF by adding the 1.7 or 2xTC, I am looking to purchase some longer glass.

My question is this: There is obviously a marked price difference between VR and non-VR lenses. Is VR something that is absolutely necessary in your opinion? My decision comes down to this argument… It will take me at least a year to budget for this purchase and I will likely have to buy a used lens. Should I choose the length and opt for a 600 non-VR or budget for a little longer and choose the 500 VR?
Thanks in advance for your advice.

Alex- In my opinion IS/VR is right up there with AF and AF tracking as a key technology in modern wildlife photography. It may be true that above a certain shutter speed, there is little value-added to turning on IS/VR. This may occur at 1/500s and up depending on who you talk to (some say that IS/VR has benefits above this). However, to take advantage of the many situations where the light is sweet but not the brightest, you will have to use a lower shutter speed. This is where IS/VR sings. You may then say "well I'm using a tripod". The problem is that even the best tripods are not absolutely rock-steady especially when you put a high magnification lens on to one. IS/VR really helps smooth out the micro-movements that are inevitable while using a tripod. So I would unequivocally say that you should go for the VR version of the super-tele you end up purchasing.

Hi Alex,

VR is necessary for super telephoto lenses. Also keep in mind that the non-VR lenses are not simply the same as VR lenses but without VR. The Nikon AF-S non-VR lenses are two decades old, they are heavy, AF is relatively slow and the optics is not as good as the newer VR lenses. You won't get good results using those lenses on today's cameras especially high res bodies such as D800/D7000. They are not worth buying IMO.

Thanks for your advice... looks like I will be saving for a little bit longer!