I know the answer is that I can not use the 2.1 SBF file to restore my phone to stock 2.1u1 after I have upgraded to the OTA 2.2 because of the changes made to the keys in the bootloader by Motorola. So I will not attempt to do that at all. My question is can I restore a "complete" backup that I made right after I rooted my 2.1u1? My assumption would be yes, since the backup was a total backup...boot/data/system/cache However I don't want to take ANY chances until I hear from the experts. This is my current scenario: OTA 2.2, rooted, deodexed, themed, some bloatware removed. One of my backups is: 2.1u1, rooted...........thats it. Nothing else done. So if I use bootstrapper.apk to boot into recovery, then wipe all partitions (boot/data/system/cache) then perform my nandroid backup, will I have success? Or will I end up going into boot loops? Just trying to start from a clean slate here and without a 2.2 sbf available, I don't wanna take any chances.