8 speed Sora3300 STI versus 9 speed Sora3403/Tiagra4503 FDs
I have two questions that I haven't been able to find a definite answer to.
First, will Sora 3300 triple STI (8 speed) work with later 9 speed series triple Front Derailleurs, i.e., Sora 3403 or Tiagra 4503 in terms of shifting/cable pull?
Second, if it will work, would chain rub then be an issue if I continue to use 8 speed chains? Should I switch to 9 speed chains to avoid chain rub..?
I'm asking because I need to get a replacement for my current 2203 FD that my old Trek 1000 came with. I haven't been too satisfied with its performance so I thought maybe I could upgrade it, but the older 8 speed Sora 3303 and Tiagra 4403 FDs are simply unavailable, around here at least.
But I will stick to a new 2303 FD if you guys think a 9 speed FD would just lead to new problems.
Thanks for any input/help!