I free feed (leave Ziwi Peak down at all times) but I also feed a home prepared diet 2x daily but only because I started feeding a home prepared diet for the chis. I have always free fed my dogs and have never had an issue. I have had all kinds of breeds. I have never had an overweight dog. I feel they aren't as food fixated when they never have to get hungry. That said, my dogs have always lived on acreage and have led very active lives.
One exception to the active lifestyle are the 6 chihuahua mixes i recently rescued (dumped family by a fast travelled road in the middle of nowhere). I have 6 female chi mixes living in kennels and getting out for 2 short walks a day. This is the best I can do until I find them homes or willing fosters.
But they are free fed a quality kibble. Not one is overweight or had a single problem. You would think these dogs would gulp food as they had been starved. But each one is a perfect body weight, even the chi/doxie mix!
Good luck with whatever you decide!