I have used Conti GP4000s for years and this is the first tire I like better. It has better ride comfort and better grip. The downside is it cuts easily.In addition you must learn some new techniques to get it mounted. The initial bead must be centered in the rim and then you should chase the other bead around the rim until you are able to mount it with your thumbs. A Joe Blow Booster pump (or similar) is required to pop the beads onto the rim - a normal floor pump won't work. A proper amount of sealant is necessary for optimum performance. The increased safety of tubeless technology is worth the hassle.
I recently purchased these and even though they came with 40mm Yksion Allroad tires installed I wanted to test out Mavic's UST tubeless. I removed one tire completely and reinstalled it. Seated within seconds using a simple floor pump. As soon as pressure got near 20 psi the tire popped into the beads. Easy as that. I deflated, added sealant, reinflated and it held air perfectly. Hubs are smooth, build quality seems strong, and although not the lightest wheels out there I dropped a full pound and a half off my gravel bike by replacing wheels, cassette and rotors.
Bought in to the road tubeless craze and after seeing a few videos, including one from GCN, decided to go with this wheelset. Haven't regretted it yet. Wheels and tires have been durable around Michigan's terrible roads, crashing through miles of broken asphalt and concrete, gliding along debris-covered shoulders, and shrugging off anything and everything in its path. The tires roll and grip very well at 80 psi, haven't assessed wet weather grip yet. Hubs engages very quickly and has a quiet but nice-sounding freewheel noise. Wheelset looks great with the aero spokes. Tires went on very easy, especially compared with my OE wheelset, where I removed some skin and blistered my hands trying to put tires on the OE rims. Very satisfied after 500 km of use so far.