Wow dude.. i can guess that you were as exited as me with getting
the combo, but then damn dissapointed when it didnt work out!
Thing is, having used the TC makes you understand that 560mm is
what you want and need, and 400 alone just dont cut it lol
Having that said.. I tried everything to make it work, and in my
case... cant say it will work out for you with the 30D body.. But
for me it went from a big dissapointment to EXTREAM HAPPINESS!
The focus is superfast and locks on target RIGHT AWAY! not like
before where oscillation was a mad problem and when it almost never
got a lock.
In good light.. not superb but still good i dont have problem
locking on birds in flight. I even lock birds with bushes and
branches around.
Its simply amazing, but as i said.. its alot of money and you
should try testing TC and XT body before buying an 30D.
I think im lucky... got a good working TC - 30D - 400mm thats
working even above expectations.. And the AF for me is worh every
single dollar i had to pay for it!
I really hope it works out for ya.
First of all.. the autofocus is ten times better then on my 350D.
Now i can acually use my 400 F/5.6L plus Tamron 1.4x TC and
autofocus on birds in flight without any problem.. that wasnt to
easy with the 350D.
Very interesting, and I'm happy you like the 30D. Could you say a
little more about the AF performance when you use the 400f/5.6 and
Tamron TC combo? I'm wondering myself if I should get a 30D because
the oscillation problem on the 350D driives me crazy.

Is there
any oscillation or does AF locks pretty quickly. Thanks for your
insight.
--
Axel
My galleries:
http://www.pbase.com/axelhi
--
Photos @
http://www.bassel.se/photo
----------------------------------------------
Camera:
Canon 30D
Lens:
Canon 400 F/5.6L
Sigma 17-70 Macro
Tamron 1.4x Teleconverter MC4
-----------------------------
Canon 70-300/4-5,6 IS USM
Sigma 18-50 2.8 EX
Kitlens
P&S Camera: FinePix F11