Sigma 120-400 vs. 150-500 vs. Canon 70-200/4,0 L USM (1 Viewer)

I am an amateur photographer that just recently got my first DSLR (60D), I do learn quick and I have full control over all my camera settings so you could call me an advanced beginner maybe.

I have a hard time deciding which to save up money for. I have not done any wildlife photography before but I know my focus will be on birds (still shots only), squirrels and other animals. I've read alot of reviews and there are so many mixed answers there is no way in hell I can come down to a decision.

Most likely I will be handholding but I do have a tripod if I decide to bring it with me. I've noticed I can get pretty close to most birds in my area, I would say anything from 3-4 meters and up.

What do you guys suggest?

Is non-IS a huge dealbreaker on the 70-200 when handholding? I got rather steady hands but I can see the difficulty of getting sharp images when handholding at longer FL's.

71 views and not a single reply. No one with an opinion?

You've have an open thread already discussing the same thing so its not really surprising no-one has replied here. Any replies to Johan's query should be posted to this thread http://www.birdforum.net/showthread.php?t=252575

JohanBorjesson said:

71 views and not a single reply. No one with an opinion?

Click to expand...

How long will you be savibg for?
Things may have changed by the time you get the money.

Vernon Barker said:

How long will you be savibg for?
Things may have changed by the time you get the money.

Click to expand...

2-3 months.

I have decided to get the Sigma 120-400. Considering the fact that I will be outside in broad daylight using f/8 to get maximum sharpness out of the lens will not be an issue for me. I was on the Canon 300/f4 L IS USM + 1.4x TC trail for a while but I am afraid of getting a prime, I would like to be versatile and it's not always I need that full focal length you know. Here are some pictures that sealed the deal for me:

http://www.juzaphoto.com/galleria.php?t=289923&l=en
http://www.juzaphoto.com/galleria.php?t=98154&l=en
http://www.juzaphoto.com/galleria.php?t=148521&l=en
http://www.juzaphoto.com/galleria.php?t=319286&l=en
http://www.juzaphoto.com/galleria.php?t=324909&l=en
http://www.juzaphoto.com/galleria.php?t=101286&l=en
http://www.juzaphoto.com/galleria.php?t=347231&l=en