There is a guy I work with who has biked for a long time. I asked him what he liked for tire width on our roads, what he rides etc.. When I mention that the bike I was thinking about was 105 with an ultegra RD, he acted all funny like he didn't want to talk down about it, but then he tells me that's why he got the bike he did, it was the only one where all the parts were "matched".

People are funny...

At least you can trust the internet right?