Re: KISS
Someone else has already made the comment about "cloudy" providers - that you may find yourself held to ransom by administrators (not the system type :-) ) or other bean counters in the event of bankruptcy or administration. Unlikely, I'd admit, in Google's case, but not impossible.
If you Go Google, there's the not-insignificant risk that they'll drop an app you've become reliant on. This absolutely MUST be factored into the analysis.
I challenge you, as a small business, to get sufficient information from a cloudy provider to enable you to carry out due diligence on their system security and resilience. If you're content to believe SalesSpeak, so be it.
Finally - your comments about Google Mail. Sure, the Spam disappears. In my experience, though, so does far too much of the email you need. Their false positive hit is far, far, far too high for a professional email system - and where's the sense in having to plough through the Spam folder looking for the emails you missed - might as well have put the Spam in the inbox in the first place. I speak as one who, with good exim+sa-exm and amavis, manages <1% false negatives and 0 (yes, 0) false positives. Which is absolutely crucial for my people. And I get the bizarre pleasure of teergrubing the spammers :-)
Biting the hand that feeds IT
