Hi--

>I recently purchased a TC16A. What do I gain and lose when using it on
>an AF body and what lenses are good with it?
>
>I know that I can't use the 'D'-type lenses. Beyond that, I have no
>clue. I'm currently using it on an F3.

I don't know if I have answered you already or not, but here goes:
The 16A seems to be as good as the excellent TC14A on some lenses
(mostly 100-135 or shorter) - and can be used on manual-focus cameras
(you can use a screwdriver to move the elements all the way forward
for infinity-focus with lenses on it). On an AF body, the only advantage
is that limited range AF is added to any MF or any AF lens f2.8 or so (or
faster - though not faster than about f1.8, or exposure will be incorrect).
It does allow simultaneous AF and MF, though - a possibly useful feature.
As with any converter, best results are with the lens stopped down to at
least mid stops. With bad matches, sometimes using f11-16 will give good
results. Have fun with it!