I've set DDG as my default a couple of times, and I find that I end up `!g`ing every search eventually. Maybe it's time to try again though.
Plus you still have to type "bookmark" <wait> "search"
Often it is good, sometimes better than Google but in some settings I too use !g frequently. I still try to use it without !g first to give some search traffic to ddg.
I hope they can use the data to improve future searches.