Here's a nice ZTR Flow EX alternative for ya... A few hundred grams lighter AND cheaper. For real?
Ryde's Trace Trail 650B rim weighs only 420 grams, which is pretty sweet for an 25mm inner width rim. The offset profile equalizes spoke tension on both sides, which, in combination with heightening of the non-dished side spoke's tension, strengthens the wheel. This probably gave Ryde the opportunity to save on some Alu, thus creating a very lightweight wide rim.
In combination with Novatec's lightweight hubs and laced together with DT's Competition spokes, this ended up being a just over 1700 grams Tail/AM set. Not bad for a 382 Euro all-in Flow EX Alternative.