I did tinyumbrella to preserve baseband on 4.1, limera1n for Jb and ultrasn0w for unlock on iPhone 4. Seems to work great. Any advantage to restoring with pwnage tool? I probably will do this with 4.2 because with the tiny umbrella method I was scared I was going to mess it up (and need unlock for Europe this semester) But it worked out well. And 4.1 fixed that nagging Proximity sensor issue.