Agreed. I experienced a big. Bug the other day that appeared like it deleted all my notes on my iPad and online and this caused me to finally bite-the-bullet and move my notes to Evernote from my offline iPhone for fear of never being able to access them again.
Was a painful upgrade experience (and the bug resolved itself in 24 hours), but I've suffered similar sync bugs over my time with Simplenote over the past 2 years and I didn't feel safe with the service anymore.