Battery draining when powered off - repair taking ages

[Nexus7_Abe]

I had a new Nexus 7 (32Gb) for Christmas. Right from the start it displayed strange error messages saying that the 'clock stopped working'. These became increasingly frequent - often preventing any reasonable use of the device, because the message appeared every few seconds. I then discovered that the battery went flat very quickly. Eventually I realised that the battery was losing its charge most rapidly in 'power off' mode (!). In just over 4 hours the battery would go from 100% to 0% - and once the battery was flat, the Nexus often refused to go into recharging mode (until half a dozen attempts had been made). The latter problem, I believe, is quite common.

Eventually I returned the Nexus to PC World, where it had been bought. They wouldn't replace it and informed me that it would need to go back to ASUS for repair. Turnaround time was supposedly 10-12 days. Well, that didn't happen and after several futile phone calls and emails from me (all unanswered!) PC World now say that I might expect to get it back in four weeks. They are trying to tell me that this is reasonable - I take quite a different view. Anyway, they have made it quite clear that they don't care what I think - there is a lesson there: do not buy your tablet from PC World if you're expecting after-sales service.

My question is this: HAS ANYONE HAD SIMILAR PROBLEMS WITH THEIR NEXUS AND/OR EXPERIENCED LONG DELAYS IN GETTING IT REPAIRED?