Last month I upgraded my Google Apps for Business so that I can have 10Tb of storage and it's US$10/month. I planned to upload 80Gb of files and stuff immediately (the important files). The pathetic upload speed and some problems outlined below means that 6 weeks on I'm only 60Gb into the 80Gb.

Google Drive's app seems to work really well, except:
1) When it's running, I cannot get cPanel to load at all on my Linux server. This took me several days of on-and-off troubleshooting including having my team set up a proxy in the Ukraine to make sure it wasn't some other problem here. So, any time I have to use the server I need to pause Google Drive (only if it's syncing)
2) The search functionality within the local Google Drive folder seems to be very limited compared to a normal folder.
3) If Google Drive is syncing, video on Skype won't work
4) It seems that everything you want to sync has to be in Google Drive, and I didn't plan this very well and now I've uploaded it I've got duplicate folder names with my Google Drive files and some other confusing stuff that I'll need to sort out.

I'm still using an external backup drive - if the internal hard disk fails I don't want to be waiting for weeks to pull down all my files again. Google Drive is more of a safety net.