I bought my son the Fenix PD36R for Christmas. I think he'll like the toggle switch better for walking the dog and the usual flashlight stuff. I also have the PD36R PRO. Great lights!
EDIT To ADD: The on/off buttons are on the tail cap of each one. The brightness toggle is on the tail cap of the PRO and the main body on the non-PRO
At contender's you liked the PD36R PRO that has the function buttons on the tail cap, and 2,600 lumens on high. For me it takes 2 hands to use it quickly. For walking a dog with a leash taking up one hand, I think my son would prefer the PD36R non pro model. The PD36R now has 1,700 lumens on high where mine still had 1,600. Not a biggie, but...
In short: You have to hold the lights differently to toggle thru the brightness levels. You'll have to ask your wife if she minds holding the PRO model at or above shoulder level or the non pro at waist level or lower, like most flashlights.