Edit:
BTW, I should probably mention that I guess the IQ with a $200 mirrorless camera like we're mentioning wouldn't be any better than with this TC assuming your 5D is a Mark II. So with the TC Adapter on then after scaling it down to 12mpx (same as a $200 mirrorless) the IQ is going to be extremely close! (I think).
Damn. You guys are on it. Thanks for all the information. I think maybe getting a 4/3 body would be the best bet. I do have an adapter coming from amazon...so I will see what I can do with it. I have a ton of hawks and eagles out my back door and I just want to be able to reach out and get a few shots.
Again, you guys are amazing with your knowledge. Thanks.