QUOTE(ReasonsofThanatos @ Sep 24 2010, 11:57 AM)
GOSH! it has backfocusing problem too??i can bear with the slow AF speed though, but not focusing problem..have to think twice then...maybe i should stick with the 50mm F1.4 plan..

yesh. especially the corner AF points. sometimes the middle also. this is especially so, if in a hurry, i straight take my camera up, half press shutter, shoot, 70% of the time it will focus the background.
however, if you have 2-3 more seconds to spare when you take your shot, then this is a very good lens.
on the A700, it performs better though from what i've heard.
prime or zoom, your call.