I use Refresh Optive in the mornings, and Refresh Tears in the evening. I don't officially have dry eye, but I have allergies and my eyes feel very dry and irritated at times.
I was using Refresh Optive Advanced, as recommended here by IKE, and that was extra thick and very soothing, but I didn't like the ingredient that made it so thick, I think it was glycerine. If I used it too close to bed time, I'd wake up in the morning feeling like I had chucks of that stuff under my eye lid. The bottle always had some hardened jelly type substance on the top where you put the cap on, and I felt that that ingredient in that amount can't be good for the eye.