I have used DDG for 4 months without finding any major snags in its operation. It is a little annoying that you have to disable the two DDG pop-up ads on all of your machines individually - and it took me a little while to work out how to do it.
I use DDG on an IMac Latest OS), my browser is Safari. I had a minor problem and contacted DDG support only to be told "We do not support Apple Macs". Ridiculous!
Sorry guys, but that is the end of my brief flirtation with DDG...