So after 5 years with an FM2 you can work here without permission? So what's the point of applying for duel nationality - which i know is a completely different thing. That was my main reason for doing it, so I wouldn't have to keep paying and renewing FM2. I suppose if I get my reply from RE before next july then I will save money as I'm only on year 2 of FM2.
Also, apparently with an FM2 you can get credit from a bank and on an FM3 you cannot. I suppose these are what the rules are right now. But they could change in two minutes.
As I understand it with an FM2 you can own property here also (without getting a bank trust). These rules have been in place for along time, I doubt there will be big changes soon. But you never know. The big change recently has been in the application of the law about who is eligible to apply for citizenship, the law did not change, but the way SRE is applying the law DID.