Originally Posted by TiHabanero

As a bike wrench I get to deal with everything every day. I am a Campagnolo user and do not run anything by Sram or anything from Shimano aside from some old friction stuff on my touring bike. Consider my opinions unbiased as my preference is Campagnolo.

The only really good thing that Sram does is wireless shifting. It is superb. Mechanical shifting Sram works well, however it is very picky about set up, wear, and dirt. Their hydro brakes pretty much suck after a several seasons, especially in the dirt. Not sure why this is, but it has been my experience over and over again.
On the other hand Shimano electronic shifting works well enough, but is a PIA to set up when compared to Sram wireless (why can't they all be this sensible?) The connectors on Shimano electronics sometimes spoil the party, and there is a slight disadvantage of a central battery when the juice runs out.
Shimano hydro brakes are very good and rarely present problems to me at the shop. By a long shot they are superior to Sram. Shimano mechanical shifting is a standard everyone lives up to and one cannot go wrong with it. Without question it is more forgiving of wear and dirt than Sram, and sets up quicker as it is less finicky.
I will take Sram wireless over anything right now, even Campagnolo (as much as it breaks my heart to admit that, sorry Tullio). I will take Shimano brakes over Sram any day of the week and without hesitation.
Thus you have my opinion. Not any more or less valid than any other opinion expressed on this thread.