My .02 :
go to a store, play with both in store. The "thin" RAZR isn't THAT much thinner than the GNEX. For me, it felt more 'edgy" in my hand than the Nexus, so that was kind of a negative for me for the RAZR. The Nexus just felt more comfortable in my hand. Feature-wise, they're both very similar. The Nexus you can use an extended battery, as it's removable. But you can't expand the memory. BUT, you already get 32 GB inside, and most people aren't going to use it up.
Also keep in mind, that while there ARE threads on the forums with people having issues with the Nexus, that's the same with pretty much every new phone. Mine has been flawless since day one, and I've had no signal issues. It's been the same as I had with my Bolt, which was the same as every OTHER phone I've had. The people without issues aren't posting nearly as much as the much-smaller percentage of people that do.
The Rezound as mentioned, is also another good choice. Slightly faster processors, decent form factor, good specs all around. But, she is going to want to hold and play with each. Also not knowing what you and she are coming from already, it makes a little harder with not knowing your experience.
Each person will have their own preferences, and it's just a matter of finding yours/hers. Take everyone else's experience in the mix, but remember again, that for everyone person posting with a problem, there are countless more without any. And not every problem is something that isn't under construction, so to speak. Just like the Nexus has updates coming that will enhance things for some people, I'm sure the RAZR is in the same boat (in fairness, I haven't browsed on the RAZR forums at all).
Good luck with whichever you choose!