Re: Need input from those who shoot Canon gear w/ TC
Without a doubt you'll get a better image from getting a larger lens...the 1.4 will be ok if you have ideal lighting. If you are looking are taking top-end pictures, get the 400 or 600mm lens. However, the 1.4 is much more affordable.
I shoot the Cannon 20D which alrady has a 1.6 conversion and might get the 1.4, If I do, I'll have a lot lower expectation on the results.
I would pose this question here for more responses:
dpreview