I've been on hookless rims for most of 3 years. (Still not riding much lately though.) I've never had a problem with burping or the tire staying attached to the rim. The opposite problem, it's a ***** to get the tires on and off. But that only needs to happen every couple thousand miles. I'm interested in how they or anything else performs while you're riding. So I put up with the difficulty. It seems like hookless is popular with carbon rim makers.
Never had the sealant dry up on me but it's cooler and more humid here.
These sound like a lot of wheel for half the money from a respected manufacturer. Lot of positives. Light Bicycle wheels are pretty well reputed around here (BF) for considerably less and name a strong case unless you're losing races by seconds though.