I've had the same bike since September. I really enjoy riding it, but I often struggle to release the battery. I've just taken it into Halfords for them to take a look, as I couldn't get the darn thing off at all after today's ride. Interested to see it's not just me.....
Have also had the battery drop out, just the once, but that's once too many.
My locking mechanism is now packed with chain lube and seems to be working ok but it does seem a pretty crude part of the bike. I always arrive at the bike wondering if the lock is going to work or not. I think it will be a good 6 months of trouble free cycling before I start to believe it will be ok.