Renewed mine online about a year ago. Absolute nightmare as for 10 weeks the site showed my expiring one hadn't arrived in the post although US Mail said it had been delivered. No way of contacting UK through email and helpline was just the opposite, kept disconnecting my calls after keeping me in line for ages. Eventually I woke up one day to 3 emails, passport arrived, application processed, new passport issued all in the space of 4 hours.

Pricing is OK though. Just renewed our Green Cards here. $630 each (x4)