The GP 5000 TL is the first road tubeless tire from Continental. After riding on them for nearly 2000kms I can say that they are grippy and puncture resistant.
Before switching to these, I was rolling on the Grand Prix 4000S II for more than 5000kms. They were and still are great. Grippy, fast and easy to install. During that time I had only one flat, a pinch flat, the tire had never punctured. But they were worn out so I had to replace them. Just in time to go tubeless and try out the new tubeless road tires from Continental.
Now about the Grand Prix 5000 TL
I have DT Swiss wheels on my bike. They are tubeless ready. I had to install a rim tape and a tubeless valve. That was the easy part.
I tried to fit the tires on the rim only with my finger as I used to do with the GP4000S2. One hour later I still could not manage to install them on any of the wheels AND my hands and fingers were really hurting.
Then I tried with tire levers. After some more struggle I managed to install them. Victory!
I pumped them up using a simple track pump. No hassle. The tires were seated properly. I deflated them, removed the valve core, added some sealant through the valve, put the valve core back, after which I pumped them back up. After a quick spin, nothing was leaking and the air was holding. Victory again!
The ride quality has improved since I can run them on lower pressure, at around 5bar (70psi). This means less road buzz or vibrations.
I am happy that I haven't got a puncture yet. If it happens, I hope the sealant does its job and seals it. My only worry is that if I have a puncture that will not seal and I have to put in the spare tube, it will be a hassle and painful. Now I always have to carry with me a pair of tire levers next to a spare tube, otherwise I will not be able to put in the spare tube.
One thing that I really don't like is that I have to pump them back up every 5 days or so. As I understood, some tubeless tires leak air faster than inner tubes, so I learned to live with this.
Note: the pair on my bike are the 28mm variety and they are actually 28mm wide; compared to the GP4000S2 28mm, that are actually 32mm wide.