Originally Posted by
Phil_gretz
In the end, wife went back to barcons. I' m definitely keeping the Tiagra STIs and derailleurs for a future build for myself.
I have Tiagra (4600) on my new townie bike and 105 (5700) on my carbon fiber road bike. Both shift very well but the Tiagra is smoother and lower effort. It feels very similar to the 9sp 105 (5500) shifters on my old bike. I've heard that since both cables run under the bar tape on the 105 it increases the cable friction. I do prefer the larger hoods on 105 and the front shifter is a little clunkier on Tiagra (but it's not a big deal.)
I've always heard conflicting tales on 105 vs Ultegra. Some people use both and say they can't tell a difference. Others say they can. On my bike there was a $600-700 price difference so it made it pretty easy for me to pick 105.