So lets say I'm buying my friend's 4S and I don't get it until next week. If I download the 5.1.1 restore image now (which I'm doing), am I able to restore it to 5.1.1 next week or it won't work?
Edit: Ok, did some reading on the TinyUmbrella site, so that answers my questions I think. So basically if I can get my friend to run TU now, it'll save the hash? And that's tied to the hardware so that when I get the phone, I'll be able to get the hash back? Testing this out on mine...
Ah, ok, so I'd just need to have him send me the files in his /Users/<user>/.shsh folder, put them in my .shsh folder, and then I could restore?
Yes. Have him email the shsh file to you. Then when you are ready to restore to 5.1.1, use Redsn0w to stitch that shsh file to the official 5.1.1 IPSW file. Once rednsn0w is done stitching the blob to the firmware file, you shift click restore in iTunes!
iClarified has fantastic tutorials. YouTube and Google are extremely helpful for first time users restoring to a firmware no longer signed by Apple. Ask questions here too if you have any problems or questions. Also, if you have recently used TU, make sure your host files point to Apple servers and not cydia servers if you're restoring to iOS5.
You're referring to unchecking the cydia options under the advanced tab?