Good for you. Any J45 will be nice, I'm partial to the ones that have the thermally aged top - feel the sound has a little more cripsness to it than the standard, and I liked that - but just my opinion. I would try to play the version you want to get first, especially because of all your comments about nut width, need to make sure it feels right.
Good luck, don't be daunted - just jump in and enjoy what you get. Worse case, you get something that helps develop a wish list for what you want and you trade it in towards that.