The rear negative camber angle for the Mazda 5 is too much for how most people drive this car. It causes too much inside edge wear of the rear tires. Look up “camber angle” on WIKI for an explanation of negative camber angle; but, basically it’s there for Zoom Zoom handling. My comment is that I have purchased adjustable upper rear control arms. ( Several distributors have the same control arm under different names. One is: PROFESSIONAL GRADE ADJUSTABLE REAR ARM ALIGNMENT ASSEMBLY 2010 Mazda 5 Raybestos Price: $ 110.99 Qty: 2.00 Part #: RAY6111187 ) These are the same as is used on the Mazda 3. I installed them myself and adjusted the camber myself to between ½ and 1 degree negative. This is a bit less than half the Mazda specification. Unlike most drivers I often drive in and out freeway ramps at near the adhesion limit of my tires. I have noticed a very slight reduction in rear adhesion, no stability loss, and understeer is still maintained. Any competent suspension and alignment place can do what I did. My recommendation is 1 degree negative. I also now have 215 50 R 17 M&S tires on my Mazda 5 with no clearance problems and my speedo error went from reading 1.5 mph high to 0.5 low, again no problem.
Quote from Think: “Unlike most drivers I often drive in and out freeway ramps at near the adhesion limit of my tires.” Unquote
Gas pedal athlete? After you park your car at work, do you run to your work station, rounding corners near the adhesion limit of your shoes?
Rotating tires should even the wear, though the excessive camber will shorten overall tire life. Interesting read, though I wonder about “I often drive in and out freeway ramps at near the adhesion limit of my tires” that must be 20 mph over suggested speed limit? (you know the sign that says 35mph or whatever.) as I am always very comfortable at 10 mph over.
If the OP’s main consideration is right turns off the freeway, he should have negative camber on the rear driver’s side and positive camber on the rear passenger’s side. That would give fabulous off-ramp understeer — if he leaves the ramp it definitely will be front first!
Double it and at 10. That’s what those signs mean. It’s just a suggestion, anyway, right? 
Stop means you, not me, and yellow light means go faster? 
Who knew an offramp was really a skid pad?