The Line 30's carbon rims have an internally width of 29mm, and are laced up to Bontrager's Rapid Drive 108 hubs.
A 54 tooth drive ring, and two sets of three pawls creates a very quick engaging hub.
I only have five rides in on the Line Pro 30 wheels, but things are off to a good start so far. Getting a set of tubeless tires installed didn't pose any major hassles, and the fact that Bontrager's rim strips are already installed helps make the process even easier.
On the trail, I'd call the rear hub noise 'medium-loud' – it's not quite as attention grabbing (or obnoxious, depending on your point of view) as an Industry Nine or a Chris King, but it's not dead silent either. Engagement is quick and crisp, and so far there hasn't been any strange noises or sticking pawls. The wheels have a nice energetic feel out on the trail, with enough compliance to avoid rattling out fillings, but enough stiffness to slap them into berms without worry.
A handful of rides certainly isn't enough time to comment on how the Line Pro 30 wheels will survive over the long haul, although I will say that there was no shortage of air time and rough, rooty section of trails on those initial outings. The wheels shrugged all of that off without a wobble to be seen, which is a promising start.
If their durability remains up to par the Line 30's are going to end up on the wishlists of plenty of riders, especially those who wouldn't mind having a positive balance in their bank account after buying a set of carbon wheels.