Cold fermentation always yields the highest quality results. Not matter whether pro equipment or homebrew equipment is used.
For enthusiasts it is not beyond reach to master. That's why I was so adamant for people to try it --- a few years back when we put all this together. Ask Bryan R what he thought of cold fermentation before I suggested it. I literally had to twist his arm to try it
Anecdotes apart, the downsides of cold fermentation is that there are some stumbling blocks. We don't know all causes and remedies here, but you will certaininly find an interested listener in your quest to perfect cold fermentation with the likes of Abbery, Techbrau and myself.
Now to your question:
Higher gravity beers will take even higher amounts of yeast to pitch, and a much more carefully conducted fermentation schedule (point of secondary transfer, residue yeast, residue extract, initial oxygen content and available nutrients). Generally speaking, getting great results at those strengths doing cold fermentation requires quite a bit of experience in the normal strength (~12 plato) region first.