I don't think shimano makes a non-hyperglide freewheel anymore so it's likely that that's what you'll end up with. Your current freewheel might use a similar design so maybe there won't be a difference but I'm guessing this is another area where the Denali cut costs.

The reason I suggested another wheel is not because it's going to make that much difference in and of itself. It's because it opens up the possibility for more speeds and an easier upgrade to brifters down the road. The current wheel is kind of a dead end. A new wheel will also allow you to use more traditional tubes.