The only thing that I didn't like about Zapier, in the trial that I did, was that I got a TON of emails from Wade Foster. I realize that you want to be connected to your customers, but an email every few days was a bit overkill. June 22, 24, 28, July 1 and 4. Too much spammy email.
There are certain kinds of data -- (financial, etc) -- that you are going to always want to run on your own locked down cluster, not uploading to google.