When the subject of 16 inch wheel bikes for communting arises there are always a number of nay-sayers all claming too rough a ride when compared to the 20 inch wheel folders.
My concern is that those who want to combine a folder with public transportation will be discouraged with toting the 20 inch models on board. The "too-rough-a-ride" label applied to the 16 inch wheels then becomes a limiting factor.
Today I went for a 10 mile commute to lunch over paved rural roads. I aired the tires up to 80lbs at the onset of the ride. I hit all the pot holes I could run across. My maximum speed per GPS never exceeded 23 mph. I'm not a light weight at 205lbs 5ft10in. The encounters that I thought might have registered as noticably different when compared to a larger wheel bike were the cattle guard crossings. For those of you who don't live out West, that is a 4ft to 6ft grate consisting of parallel bars or pipes placed over a pit in the road to keep cattle and horses from crossing. They are a bit jarring on any bike.
CONCLUSION: Not a bad ride. The ride difference it seems to me is more theoretical then real. I would not discourage anyone from the 16 inch wheel for moderate communting distances over average paved roads. Now doing a century on a 16 inch folder may be a completely different story.