Still too early for me to offer an authoritative comparison, but I have two Ridgeback Panorama touring bikes. One with rim brakes and a new one with discs.
Although I loved the old one, I chewed through front and rear rim brake pads at least twice a year and a set of rims lasted me about two years, even though I only do about 3,000 miles per year. Being a super-heavyweight rider, I had the stopping distance of an oil tanker.
I'm hoping the disc brakes last me a bit longer and save me money on replacement rims. But even if they end up costing me more, I'm already finding that they have transformed my ride experience. I do not ride fast or tend to enter sportives or anything like that .... just regular hilly club rides and audaxes, carrying a lot of weight. I was getting tired of having to jam my brakes on harder and much earlier than everyone else I ride with when descending hills, and tired of the sniggers at the squealing noise they made, alerting everyone to my approach before I ever came into sight. The discs are just so much grippier, quieter, and they take less effort and don't leave me having to decide which hedge to aim for if I meet a car coming the other way on a narrow descent.
I am a convert, however the price comparisons stack up. Still early days, though, and I'm sure I will encounter things I've not yet thought of, but I'm 100% sure at the moment that it will be the disc bike I'll be taking to the Vosges this year. Can't wait to let loose on some long descents instead of cramping my hands up for minutes on end struggling to keep the speed down.