Telephoto lens dilemma

I am trying to decide on a telephoto lens to use for wildlife photography. I have basically narrowed it down to this field.

Canon 300mm f/4 IS
Canon 400mm F/5.6
Canon 100-400 IS

So which of these would be best for wildlife? The 400mm sounds appealing to me because of its great auto focusing speed and IQ. It is also light enough that I could probably use it handheld with few problems, and I will most likely have a monopod in general anyway. I like the idea of having the 300 also since it would let it more light for morning and evening deer shots. The downside is that I would have to use a TC in order to get the reach, and sacrifice some IQ. The IS is also a bonus of this lens. As far as the 100-400 is concerned, it seems to be the most versatile, but I have a feeling that I would be using the long end in general, so I wonder if the prime IQ advantage would be greater then the versatility. All thoughts and experiences would be appreciated.

FYI: Budget is around $1000-$1500

300 f4 plus a 1.4x convertor. I've used this combo, and believe me it works great.

I use the 100-400 for general nature photography. It's versatile and light enough to hike with, plus the IS helps a lot as light starts to fade or in the shaded woods. Speaking of that, if you plan on being in the woods, I would suggest IS on whatever lens you choose. It's often difficult to get decent handholdable shutter speeds in the woods, even on a bright sunny day.

Thanks guys. I am in the woods about 80% of the time, and will probably do most of my wildlife work there. I shoot deer much of the time, and some birds and turkey.

If you have comitted to use a monopod, I would get the 400. The 400 bare will have better IQ than the 300 f4 with a TC, or the 100-400. Also, if you need the extra reach at the expense of some IQ, you can always buy the cheap Tamron 1.4X TC and retain autofocus. The 100-400 is very versatile and also smaller and easier to carry, but if IQ and focus speed is important, I think the 400 5.6 is the best choice for you.