Advice on SBS 2003 R2 migration to Office 365

Hi Everyone,

I'm considering moving Exchange services of a a client's SBS 2003 server to Office 365. There are a few questions I have for the pros out there:

1 - Can SBS 2003 run smoothly without Exchange? Is it better to disable Exchange services or completely uninstall? The only requirement is to keep SMTP services to get SBS reports and other servers that send reports via the SBS SMTP.

2 - Active Directory Sync Tool and Active Directory Fededration Services (ADFS) -- will they work on SBS 2003 R2? Any known issues?

3 - As with most SBS 2003 servers (assuming here), our domain name is XYZ.local, and as I understand, it will be necessary to create public UPN such as XYZ.com -- Seems straight forward, but is there anything specific to SBS 2003 R2 to add to this?

Anything else anyone has to add about migrating from SBS 2003 R2 (or similar) to Office 365 would be great to read up on!

Thanks in advance.

ERG