I updated my tablet a few weeks ago, using the UK version.
It's been good, but I noticed that Kies kept saying that my device could not be updated that way.
I really wanted to get my system back into US mode, so I've been impatiently waiting.
Yesterday, I downloaded the XAR version. When Kies still sneered at me, I tried installing it using Odin 1.85 and my cable. !!Success!!
I didn't lose anything, Keis now likes my tablet again, and it all looks good.
Can't believe how easy this was, after all the fears and stories of bricking.
So --- where is the official Jelly Bean rom?