Not at all. That is the 2.2OTA Bootloader and you are good to go! 30.03 or 30.04 are fine.
Yes, the SBF does
not update the bootloader. If you want to update the bootloader you need to run the update.zip. I don't see any reason to at this time however.
Personal preference I suppose. I SBF between Roms almost daily. I just prefer it. I am lazy and I like to click the button and just let it go
Just in case you guys weren't aware TBH released the update.zip on 11-20 and there were many people who didn't follow the directions properly and it resulted in bricks with no possible fix. As the numbers of bricked devices became higher and higher TBH continued to try to find a solution. This leak that we are lucky enough to have today
is that solution. It wasn't originally intended to be released but this seemed to be the only way to recover these bricked devices.
If you flash the update.zip be extra sure you follow the directions properly or you may end up with an error-ed boot loader. Luckily we now have the full SBF to recover if it happens but you still need to be careful and follow the directions closely just to err on the side of caution.
GMB