It's so sad that all the worst aspects of this game have tiny little sparkles of goodness that you might just be able to spot if you squint your eyes and turn your head. For example, the mach speed sections could've mirrored the awesome breakneck speed trips in Unleashed, if not for the fact that every single control was broken. Am I exagerrating? No. The jump button locks Sonic in place, unable to move right or left or even control his forward trajectory. The control stick sends him flying off the edge of the screen at the slightest touch. The light dash button (not mentioned in-game, ever) randomly chooses whether to work or not, and half the time a line of rings will lead you straight into an obstacle. Worse, absolutely every object that isn't flat ground (and sometimes that, too) will instantly cause a loss of rings if touched.
Sonic 06 is an obvious beta. A very obvious beta. Unless it's an alpha. If it had been finished before being rushed to stores, we might've found something good, or at least passably mediocre. As it is, it's exactly as bad as others have claimed.
Bile fascination and narm might just push this product into so bad it's good territory, though, so it might be worth a rental, if only to see for yourself just how bad it is.