It probably wont surprise you to know that I get asked this question a fair bit, it probably also wont surprise you to know that the answer is 'talk to the vendor you got the phone from'.
Theoretically its possible to get most Windows Mobile 5 phones upgraded to include MSFP but the decision in the end is with the vendor that supplied you with the device in the first place. Take a look at the announcement here names a few companies that are looking to offer free upgrades to Windows Mobile 5 users that want MSFP.
The following either have devices with MSFP already installed or plan to be released soon
Is it worth mentioning that the iMate phones include the O2 XDAs as well as orange's own SPV series?
It is indeed. The thing that needs to be considered is that a number of these phones come from HTC first and then get rebranded and sold via guys like i-mate as well as the operators. Even though these devices look the same you need to go back to the company you purchased it from e.g. i-mate OR your operator and get the update from them.