I have ridden Shimano all my life. From mountain bike to tri to a decade of road racing. It's easy, crisp, and ubiquitous. I abruptly stopped riding for almost 10 years and started back up this spring. I bought an older (2001) handmade steel bike with Chorus. I'd always wanted something like that.

I like swapping parts around, shopping for great used deals, fixing stuff myself. I had to buy some new tools to do it. As almost nothing on the local Craigslist fits my bike. The local bike shop will not have parts.

I sure like the shift action of the ergo levers. The brakes have clearance for 28 or 30mm tires if I want. I don't have to adjust the bike hardly ever. My old (late 90s to 2008) Shimano DA and Ultegra stuff needed a tweak just about every ride.

I find Campy to be loud if out of adjustment. Shimano seems to slip if it's out.

I can't speak for any of the newer stuff. My Campy works better than Shimano. I'd never tour on it, too hard to service or replace parts. From home with time and the internet on your side, I love it.