First of all, the weight. My set weighed in at 1,266.4g including rim tape (544.4g front, 722.0g rear). As far as I know, that makes it the lightest stock tubeless wheelset on the market.
Some of you may be apprehensive about carbon braking, but no need to fear. The rims are actually just rebranded Reynolds Attack rims (they actually have a Reynolds logo on the rim as well), and combined with their Power pads, they actually have a higher initial bite than alloy brake tracks. Total power once you really get down in the lever is about the same, but the bite definitely inspires confidence. Do note that this is for dry braking, I haven't been caught out in the wet yet, although other folks have said the wet braking is also really top notch.
Next is the hubs, although i9 doesn't have the same cachet as DT Swiss or Chris King, those folks over in Ashville, North Carolina definitely know what they're doing. Obviously US manufacturing doesn't always mean best in the world, but in this case, they really take it with pride. There is no preload system to mess around with, they just work. They roll on high grade Enduro bearings with no special proprietary sizing. A full bearing kit for the front and rear is actually sold for only $60! The rear is also laced 2:1, which means there are 16 spokes on the drive side, 8 on the non drive. This means the tension is pretty much equal on both sides, which leads to a more balanced wheel. The 16 drive side spokes also lead it to have the stiffness of a 32 spoke wheel (in theory). I don't weigh enough to flex them much (125 lbs/56.5kg), but they do definitely feel more spritely than most other wheels I have ridden.
Compatible with tires anywhere from 21 to 35mm, they're a super versatile wheelset that will take most anything that you can throw at them. They also do ship with tubeless tape installed, so if you want to try that weird stuff, its an easy setup as the rim does have bead shelves for easier tubeless tire inflation. Compatible with everything from 8-11 speed with the included spacer. Small note is that skewers are not included.