I am kinda torn between two lenses that serve kinda different purposes.

I have around $1000 to spend, and want to decide between the :
Sigma 150-500....And
Canon 70-200 F4L IS

I am a hobbiest, kinda not very experienced. I shoot mostly landscaping and wild life. As well as my kids soccer and basketball games.

I currently have the EF-S 18-200 (which I think is a really good walk around lens)

I have the Canon 10-22 Which serves great for wide angle landscaping.

I have a 70-300 USM IS and it's a really good copy (I think)

And I recently bought a good copy of Sigma 170-500 (but it made me realize the importance of IS)

I have two TC: The Kenko pro 1.4X, and Tamron MC7 2X.

So how would you spend this $1000?
should I go for the very high reputation 70-200 f4 IS for an L glass, with probably better picture quality than my 70-300 USM IS. (And maybe use a TC to get wild life shots)....I can get a lightly used one with UV and CP filters for $900

Or go for the longer range NEW 150-500 Sigma and get the benifit of the IS (which I miss on my 170-500 ) ?

Thanks in advance for your input and help


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Canon 50D, Canon EF 28-135mm , Canon EF 70-300mm , Canon EF-S 10-22mm , Canon EF 100mm f/2.8 Macro USM, Canon EF 50mm f/1.8 II, Canon EF-S 18-55 USM II, Canon EF-S 18-200 IS, Kenko pro 1.4X, Tamron MC7 2X