fortigate utm vs fortimail?

Sorry if this is an FAQ - I've not seen any posts that answered this.  I currently have a vsphere VM running sophos-utm as an SMTP spam/av proxy, and have become unhappy with the amount of junk that gets through.  I've heard good things about fortinet, but am confused by the difference (if any?) between fortimail (virtual or physical) vs fortigate with UTM license.  I am currently using a pfsense firewall, and have no inclination to switch, unless that went with switching to fortigate+utm.  I seem to get the impression that fortigate+utm is less featureful, is this true?  e.g. providing a per-user quarantine, and other things, whereas fortigate+utm would mainly just tag the messages with a SPAM header, and my MTA would sort those into junk folders (and I'm okay with doing that, if needed).  And if I went with fortimail, I'd be inclined to go the VM route, if only because I can back up the appliance easily, using veeam.  Any thoughts/tips welcome!

Agreed
 
The two products overlap but fml is more advance. Also to add  FML can be a smtp-gateay or server , grey listing and has better logging and mail tracing features that you can't get with a on firewall FGT platform.

One disadvantage to a fortimail HW appliance: apparently the low-end 60 is end of sales now (and soon to be end of support).  The next cheapest supported appliance is $$$.  Trying to figure out if the VM-0 (sp?) is feasible.