I'd always go for a Rhyno Lite XL. I love mine, plenty strong enough for streety trials and only weigh just over 500g each - quite thin in some people's eyes though at 29mm, could always look into Tioga DH rims - they're 35mm wide so would be pretty mint out back, and are pretty similar weight wise to an RL. Mate those to a set of ProII's and you'll be set! The front's only about 50g heavier than that Echo hub and, in my opinion, far better looking and will outlast it, my echo hubs died a death bearing-wise after about 6 months and i barely rode the bike...