Stans Flow, if you want strong but reasonably light... Not UST but once taped up with the yellow tape they function exactly the same as UST. Lighter, wider and stronger than an 819, and not IMO any less strong than a 721
Expensive though... Would probably end up making more sense to sell your wheels and buy another set.
Expensive though... Would probably end up making more sense to sell your wheels and buy another set.