I've only had my 2014 Limited with auto running boards for a few months, but I specifically asked for the auto running boards when I traded for the 2014. Various family members had trouble getting into my 2013 Limited that had no running boards. I leave them turned off when it's just me in the truck, but I like having them available for when others are riding with me and need them.
I only do very light offroading while camping, so sliders aren't a necessity. Add in that I personally just don't like the look of the fixed running boards (I feel they make the truck look bulky), so auto running boards were a good fit for me.
Note that the auto running boards are a factory option, so you wouldn't be able to add them later if you opt against them now. I contacted a few aftermarket step providers regarding my 2013 Limited, but they all said the 4Runner was too low volume of a vehicle to justify something like is available for other trucks.
Here are a few pics of the running boards on my 2014 Limited with Michelin LTX M/S2 tires on the stock rims. The driver's door isn't fully closed so the running board will stay out.
Hope this helps!
-BK