Some points from my understanding of this:
1. Dextrose is indeed Glucose and although it helps to take it post-exercise, it is all the more important to take it WHILE exercising. It will prevent glycogen depletion during exercise and prevent what is known as a "bonk". Most major market sports drinks (Gatorade, Powerade, etc) contain Dextrose as their primary carb source.
2. Some folks don't like Dextrose in their sports drink because it causes insulin spikes and burns too quick giving you cycles of high/lows during exercise. However, maltodextrin is glucose containing chains of sugars that digests more slowly to provide a more even/consistent carbohydrate source.
MacBruver...your Endurox R4 actually contains Maltodextrin, not dextrose. Most higher-end sports drinks contain maltodextrin or some mix of maltodextrin and dextrose. Maltodextrin is especially important for endurance athletes as +3hr rides with Dextrose containing Gatorade doesn't work out so well!
3. For recovery, its more important to have something containing protein as well as some carbs, instead of just carbs. Dagatris chocolate milk is a great/cheap option, and the current trend is to put protein into sports drink to take during exercise. The jury is out on if this really helps though. Long story short: for recovery...you want protein as well as some carbs.