Hi folks

I have tried SME 7 last year, with an eye to use it as a email server but I didn't manage to push through due to contraints (from above and situation).
Anyway, I am looking into it again, but I thought I try to solicit some feedback from you guys.. anyone using this primarily as an Email Server only?
Overkill? or too risky? I am deploying it for a company with about 30 domains with about 300 POP accounts, and countless forwarding account.
The machine I am looking to replace it with SME is running PLESK control panel for email. Essentially, they both are using the same webmail (Horde) but somehow.. plesk can be quite a pain to backup and restore (if need be). SME seems to fit the bill since it is a hold OS... but I am not sure how easy it is in that aspect.
Is SME capable of such a production deployment?
Primarily, I am looking at something which can allow me to do backup/restore/maintenance easily, able to install it with some form of redundancy (I think I read about RAID 1 capability for this SME, so that should be fine)... and most importantly.. something which can be stable enough (heh, don't we wish all apps out there are such)
Oh yah.. anyone manage to deploy a pair of SME servers to mirror each other email accounts creation such that one can takeover (by having multiple MX records)...?
Ok enough of my blabbling, I really look forward to hearing from you guys!
Thanks!