Light Bicycle*
Nextie
Speedsafe*+
Carbonfan*
Oxive
EIE
BTLOS
Elite (Elita One)
BXT*
Tideace*
Pro-Mance*
Hongfu*
TanTan*
Xiamen Carbon-Speed*
Angle Sports*+
Larath
Dengfu
ICAN*+
CSC
Bitranz
Fitlite
Trident Thrust
*people I've communicated with directly about wheel builds and/or rims.
+people I've bought wheels/rims from with positive experiences
If you're looking for exceptional service and customer experience, go with Light Bicycle. Quite a few customers with issues though over the long haul.
If you're looking for top-notch product quality but at a price, go with Nextie, Oxive, or Carbonfan.
If you're looking for the ultimate weight weenie experience, go with Speedsafe.
If you're looking for niche offerings (650B fat, 90mm fat, 50mm plus, etc.) check out Light Bicycle, ICAN, and Xiamen Carbon-Speed.
If you're looking to save on shipping costs while buying a frame, go with sellers that also sell frames (Hongfu, Pro-Mance, Dengfu, ICAN, TanTan etc.)
If you're looking for a dirt-cheap product that's tried-and-true, go on Aliexpress and search "29 carbon rim", sort by "orders", and look at the first three items that pop up.
Finally, if you're looking for something that doesn't exist, talk to Xiamen Carbon-Speed about opening a mold. They only cost about $1500-$2000 deal done. Anyone want a 120mm-wide carbon fat rim?
Pretty much anything on Aliexpress with more than 10 orders and 4.5+ stars is good for a try.
All of those companies offer monocoque (meaning one piece of fiber) rims in various widths and depths with either asymmetric or symmetric construction, customized hole drilling, and many of them offer wheel builds for what works to around $25 labor per wheel. Almost without exception they all offer at least 1 year warranty.
I have yet to find a non-legit seller.
Most of them order mass production runs from the same factory with very similar molds designed by the same engineers and laid up from the same rolls of fiber, get their products stored in a corner there, ship to their office quarters for QC and warranty before shipping out, and then ship to you the customer. Mass production generally means between 50 and 200 pieces, based on my communication with a factory (forgive my natural curiosity about the inner workings of the industry). This means working through a brand is your best bet--their prices are reasonable as is.
Light Bicycle and Nextie are different in that they have in-house product development and manufacturing. I don't know about Carbonfan. Light Bicycle operates very autonomously, but I find their prices hard to justify any potential increase in quality, since there are quite a few customers with issues.
There doesn't appear to be much difference anymore in the quality of the product from brand to brand, it's mostly in how well it's marketed and quality of customer service. There isn't much thank for loyalty as profit margins are razor thin and American-style marketing prowess is fundamentally lacking.
