I have now accumulated around 1300km on these wheels. But about 50% of that was indoors, however, when there was snow and/or bad weather outside.
But I've done around 500k outdoors in just these past three weeks alone on various terrain and in various conditions: Flat terrain, very hilly terrain, zero wind as well as a very windy ride with particularly strong gusts. Here are my key takeaways so far:
The weight: This is the strong point of these wheels, obviously. Being so light, they feel amazing uphill. Even on slight inclines when powering over small crests I feel it is very noticeable that there is very little resistance to accelerations and the bike just feels extremely light footed in general.
The stiffness: The wheels' strong point is also their weak point. Obviously, if you built a rim like this with carbon spokes, it would make for a much stiffer wheel. Sapim CX Ray-spokes aren't the stiffest to begin with. Pair this with a - probably - less stiff rim and you do feel that there is some give. They don't feel inefficient. They're definitely stiff enough for climbing out of the saddle and the occasional sprint. But if you want something with minimal flex under high power-efforts like sprinting, you might want to look elsewhere. To me, these strike a very good balance between comfort and stiffness.
Durability: I'm not a light rider. My weight varies between 80 and 85kg. My FTP is usually somewhere between 300W and 350W depending on the time of the season and my training. I am not an explosive rider, more of a time trial kind of guy. I was wary of the weight limit with these and found myself nursing them down descents on bad roads at first. But I think it was all in my head. After a while you kind of just forget about it. Some of the roads in my area are really pretty broken, super bumpy, open cracks and giant potholes on descents that you have to negotiate. There's also the occasional stretches of cobbles. I've done it all on these wheels and there is no sign of them running out of true. I'm pretty confident (SO FAR) that they hold up fine.
Riding dynamics and cross wind stability: To me, these are perfect allrounders and I particularly love the way these ride in hilly terrain with short steep ramps. Being a heavier rider, these really help me power over short pinches and keep my average speed high on hillier rides. The lack of inertia makes these just go uphill effortlessly. But it is also what makes it feel slightly less satisfying on the flat. It might just be in my head because the numbers do not really show them to be much slower on the flat than my 55deep wheels. But it's just the way they feel. I definitely agree that they feel more stable in cross winds. I'm a heavier rider so I don't really have much trouble with winds to begin with. But these feel particularly unaffected by cross winds. I did a ride with super strong gusts and apart from one time where the front wheel on a very fast descent got slightly upset by a wind gust, they felt literally completely unaffected. I got 60mm deep wheels on my rim brake bike which feel much worse in those kind of conditions. However, the very light weight and lack of inertia in my experience makes them feel more nervous on descents through corners and over bumps. Less weight just means less gyroscopic force, if that makes sense? So at high speeds through corners, these wheels react more nervously against steering impulses and are easier upset through bumps in the road. You do get used to it but it's noticeable.
Conclusion: These are great allrounders which make for a worry free wheelset to be ridden on all kinds of terrain and in all conditions (on the road, that is). They seem very well made for the money. I'd only really advise against these if all you ever do is riding on flat terrain. That's where these just feel less exciting to ride.