[PRL]

As most here, I'd advise to go for a commercial service. Selfhosting is fun but can cause unnecessary headaches.

Fastmail seems to have an impeccable reputation. I have been using sherweb for several years now. Works very well. It's a bit more expensive but you also get a lot more, too. Think calendar, contacts. Plus, most smartphones work wonderfully with the Exchange mailbox. They are located in Canada. Last but not least, the webmail interface finally works well in other browsers than IE. http://www.sherweb.com/hosted-exchange/hosted-exchange-featu... They also support IMAP.

Are there any good hosters based on Zimbra out there?

[peacetara]

For zimbra, I've used http://www.simplymailsolutions.com/

They are based in the UK, so you have to convert their pricing, but Their service has been fabulous. It's Zimbra. I eventually ended up moving to iCloud, with my new phone, I ended up losing some income streams, and wanted to cut down costs, but otherwise I'd still be with them. There is also 01.com, I used them some too, they are fine, if you need a US based provider.