Quote Originally Posted by sedwards View Post
ive been reading a lot of reviews on line and cant really find a true answer. some say to put tape on some of the pins but the canon website says in wont work on my camera. has anyone used one on a rebel series camera if so how bad is it when they say autofocus is slow ? ill be getting a new lens in about a month , either a 300f4L or 400f5.6 and im thinking of an extender for a little extra reach for when the critters are a little far.
Step 1: buy the lens you want.
Step 2: use the lens you bought.
Step 3: buy the TC.
Step 4: tape the pins if you bought the 400/5.6L and you want AF.
Step 5: use the TC.

You're at step 0.5. Long way to go before taping the pins is a factor.