My experience has been positive.
I have an air compressor, seating tyres is a breeze. While this might sound bullsh*t to some people, i'm using the same Stans sealant that i've bought 2 years ago. I've actually re-used some of it in when I switched tyres. A minimal amount dried up in the tyres, the rest of it is still perfect. I don't clean out the valve cores. While they clog up just a bit, I can still pump up the tyres and get an accurate pressure reading.
I haven't had a puncture in 2 years. When I changed tyres I noticed 2-3 holes in my tyres which I didn't even know about until then. I bottomed out the front tyre plenty of times where i'm sure tubeless saved the day. Keep in mind, i'm not as hardcore as some of the guys here who might ride hundreds of miles every week.
Personally i'm not sure if i'll ever go back to tubes since luckily I haven't had to deal with the hassle side of tubeless (yet).