Over a year ago, it was definitely a rough start for me with the GG: My single, most nagging and chronic issue was the endless "Waiting to prepare..." message. Oh, how I struggled!
A couple of resets and Network Services restarts later, me and my GG were humming along. For a while, when my GG couldn't connect to one of my HD-DVRs, restarting Network Services always did the trick. After the device was running fine, I experienced a major issue several times: While in-transit, the GG client would all-of-a-sudden lose my account details and because I wasn't internet-connected (e.g., I'd be on a flight), it would invalidate and delete all my content!!!
I run my GG client on a Windows tablet and the problem always seemed to occur when I'd put Windows to sleep, so from all indications it seemed like a GG software bug when it came out of a Sleep. A couple of times it happened outside of Sleep, so then I wasn't really sure what was causing the issue. Anyway, the problem became so persistent that I eventually bought a backup drive and prior to my commutes, I'd copy all the downloaded content to the USB drive, Sure enough, when the problem occurred, I'd just re-copy all the content--but only once I arrived at my destination, where I had Internet connection in order to validate my account.
It has been forever since that problem re-appeared, but I can't do without my content while I'm away, so I still take backups on the USB drive. So, for me, it has been smooth sailing for a very, very long time.