If your already a dextrose user, then do it. Im not gonna tell you to spend hard earned money to avaoid any potential sweetners. Are you asking about dextrose in general, or just if their is something wrong with this particlar product?
I don't see the point. I feel better, look better, and perform better using a nice complex carb after training. Just because something is what's always done doesn't mean its always right.
When you've made your alterations from whey to whey+oats to whey+dextrose, what have you noticed? Were they isolated changes so that nothing else could have affected your results?
I'd say that would be your indicator as all bodies react differently. If you're looking to cut and work out later in the day, there's nothing wrong with just rocking protein and going without carbs. But again, I'd say let your past results determine what route you go.
************************************************************************Some things that need to be cleared up:
Muscle glyocogen replenishment doens't NEED to be as fast as possible. Whether the carb source comes from dextrose, frucutose, sucrose, lactose or whatever, the rate of proteins synthesis remains the same. The negative effects of high GI at large amounts just rear its ugly head over time.