@ojay
It depends.
If bp is not touched,there's no need to edit seems.
Well here's what happened:
I had stock 33P firmware on my phone, and did some seem edits to enable the 850 mhz band. Then I flashed Ultimate (BP and AP if I'm not mistaken) and my 850 mhz band was still working (from the F/W upgrade or the previous seem edit?) so I didn't touch anymore seem edits.
Now, I just picked up an EDGE sim card and debating on EDGE service, wouldn't mind having my ROKR running as long as my 850 mhz isn't touched...