I'd second JoeyD20 on the idea of taking time off it for a month every once in a while. I haven't seen it studied, but it just makes logical sense to stress your recovery system like you stress you other systems (e.g., aerobic, lactic acid, creatine) to get it to work more productively.
If you always prop it up, your body doesn't have any reason to adapt by producing more glycogen with a given level of input or your muscles get better at taking up glucose and protein without dumping a lot of glucose into your system.
I could be totally off here, and would love to see any studies one way or the other on this.
I'd also add that unless you are planning to become an elite athlete, you will have to prudently weigh the overall health impacts of anything you consider doing.
You don't necessarily need to squeeze out that last 10% (I'm making the number up) out of your post workout drink to make good progress over the long run. You also have to weight the possible added expense, and whether your efforts & money would be best used on other measures like additional equipment.
Finally, the other thing that concerns me with dextrose/maltodextrin is that the insulin spike it produces also leads to a big blood sugar crash more quickly than other carbs. This doesn't mean don't use it, just be aware that you will probably need to follow the dextrose/maltodextrin with another smaller dose of less quickly used simple & complex carbs or you will end up in a catabolic state when your blood sugar begins to drop.
I like to get my quick boost (maltodextrin & protein centered) just before the end of my workout, then follow it with a second drink right after finishing that draws its carbs from a mixture of sugars, a bit of fiber, and more protein. A fruit smoothy (a little OJ, banana, frozen berries, plus sugar or honey, nonfat yogurt or skim milk, and whey protein) does the trick.
If you make a pre-mixed recovery formula, save a portion and drink it 20 minutes later, or better add it to some sugar rich whole food like fruit juice or skim milk. You may need to adjust the amounts you use to account for the additoinal calories you get from the juice, fruit, sugar, milk, protein powder, etc.