A Small Dilemma Re Telephoto Zooms

I'm looking to move to a faster telezoom shortly.

I was hoping some of you would be able to provide insight into which lens would be the best purchase. This lens would have to serve as a wildlife, portrait, and landscape lens, hence the dilemma. I'm looking at the Canon and Sigma 70-200/2.8, Canon 70-200/2.8, and Sigma 120-300 non-OS. My thought process thus far is that the 70-200/4 is the best for landscapes, the Canon F/2.8 is the best portrait lens and is functional with TCs for wildlife, the Sigma 70-200 is a decent budget compromise for portraits, and the 120-300 is best for sports and wildlife.

Budget allows for the Canon 70-200/2.8, but I'm thinking the Sigma 120-300 would be cheaper, longer (obviate a 2x TC, also making it cheaper) and IS is less useful with such a heavy lens, while the Sigma 70-200/2.8 isn't that much worse than the Canon and cheaper still. Even though I can afford the Canon, I'm looking to get a TSE-24II, so less is obviously better.

Thanks in advance for any insight.

70-200 2.8 IS mII.

Sp1207 wrote in post #13361321
IS is less useful with such a heavy lens

Er, you mispelt 'more'.