Take a close look at the FD cage. My 105 was damaged by several chain sucking incidents. I had to bend the front of the cage back to it's designed location. Since these are aluminum, I didn't expect it to last much longer. I replaced mine (wish I had purchased the Ultrega version... only $15 more). I did get the newer 105 version... very easy to replace. Next year I'll replace my FD to match my new Ultegra RD... also easy to replace.

As I replaced the FD, I noticed my cage was actually broken! I had to look closely, but the horizontal piece connecting the outer and inner cage pieces was broken. So under no pressure it would shift fine, but when there was tension on the chain... not so good.