I was fortunate enough to try a sample of this recently and wanted to throw out my opinion.
1. Taste was good. The sample I tried was 2 servings and I mixed it into a 20 oz bottle. It was a tad strong at that concentration, but it's be perfect in 32 oz or so.
2. Mixed very easily.
3. No residue/grit.
I am generally not a fan of any lemon flavored powders, but this one was smooth and not overly tart. I give it the Rodja seal of approval.