Experience with HealthNet Canopy Care HMO?

I've had Kaiser insurance for over 15 years and we've been overall happy. That said, we've noticed that we're ready to have more choice and access in terms of specialists. The cost for a PPO through my work is astronomical, so we're considering HealthNet Canopy Care HMO. This would still have predictable costs but we'd have access to Sutter and UCSF specialists. I know this is relatively new plan. Has anyone in the East Bay Area had experience with this plan? We live in Oakland and would seek primary care in the Berkely/Oakland/Walnut Creek/Lamorinda area. I would especially be interested in hearing issues with billing/payment (benefit of KP system is you never have to mess with this!) and options for maternal care. Thank you!