Dextrose is popular because it is high glycemic index, but glycemic LOAD is more important for total insulin secretion. I large meal with carbs and protein is ideal imo.
I still use dextrose in my intraworkout shake. It's dirt cheap, tastes good, sits well with me and seems to give me energy to keep on going. Usually 50/50 mixed with karbolyn, but sometimes alone.
I have been using it instead of waxy maize. The waxy was not sitting well in my stomach and I had some dextrose sitting around so I switched to dextrose and no more sick stomach feeling now. Waxy and karbolyn just made my stomach upset for some reason.