| - expensive and limitation of option plans
This stopped me from becoming a paying customer for years. I had 20GB of free space from referrals and it's a big leap from not quite enough space for nothing to too much space for a $100/yr. I started using the free space from Google and Box for my overflow while waiting for Dropbox to offer a $50/yr plan... and I blinked first.
The Google and Box clients are serious contenders for dethroning iTunes as the worst software on my computer. Dropbox just friggin' works and I've never noticed it crash or have a negative impact on any computer I've put it on.
My first renewal is in four months. Maybe I'll find some time to give ownCloud a try before then... or maybe not.