Well, I received the Wilson Electronics Sleek signal booster today.
First the good. I went from 2 bars to 4 bars instantly with the phone in it. I'll figure out how to check the actual signal later tonight.
Now the bad. One of the bottom rests sits immediately over the headphone jack. I'm considering just cutting it off (phone will still be secure), but not until I head out to our ranch this weekend and see if it really boosts the signal enough to justify keeping it. Adjusting the site clips either way doesn't free this up enough to expose the jack.
The volume buttons just barely clear the left clip. Not the easiest access... but nothing that would be a major problem. The power button clears by a lot.
Now the side clips (using the medium-sized ones) don't extend immediately over the screen at any point, yet it does make it a little difficult to hit the letters on both edges of the keyboard.
I have the Diztronic case on the phone. If you had a larger case such as an Otterbox, typing probably wont be hindered as much.
Also I was under the impression it came with a vent mount, but it only comes with an adhesive mount. It will swivel 360 degrees.
Final thoughts: As a signal booster it seems to work great, especially when only $85 from Amazon. As a car dock, I dislike it. Between the rest covering the headphone jack and the clips somewhat inhibiting typing, it doesn't fit the Nexus as well as I'd like. I'm thinking of returning it and getting the adjustable Pro Clip (pictured below). However there's an area at my cabin where I get great bars but can rarely connect... if this allows a good connection I may keep it.