From Sonic, Sonic 2 and Sonic3&Knuckles comes the sequel we have all waited for: Sonic the Hedgehog 4 - Episode I, where the franchise goes back to its roots to try and redeliver the classic momentum based platformer that carried Sega to success in 1991.
Unfortunately the game does not deserve the complement of its predecessors as for the most part the game insults the classic era of the franchise with a mediocre game that has a inferiority complex - trash can't disguise itself amongst gold.
The level design does not complement the momentum and even the momentum mechanics of the game are poor or rather broken and don't hold their own to the older brothers which will leave you with nothing but a sigh as the game spoonfeeds you dash panels so that you don't earn your speed and you're not punished for mistakes.
The developers don't understand that earning your momentum gives you a fresh experience when you replay the level and you understand the layout well enough not to crash into Badniks or spikes which is why the ring system is there in the first place; so you can fail multiple times, learn from your mistakes instead of punishing you downright so once you finally learn you're allowed to hold the reins of speed and all its goodness.
Taking that away devalues what made the classic games in the first place. The game also introduces the homing attack that is forced on you and drops every bit of speed you've gained so far.
Despite what has been said about the level design, Zone 4 takes a few steps towards the right direction but it doesn't stop the game from falling on its face, you also have the terrible floaty physics and the poor (re-)designed bosses to also thank for that.
The music however is great and with the beautiful visuals are very reminiscent of the classic Sonic games are by far the strongest points of this product which thankfully don't collapse with the disappointment of the game. Even the 2.5D models are great other than Sonic's model itself oddly enough.
What makes this game bearable is the fact that it's a average platformer game when you don't compare it to its far superior prequels, the length is very great for its price and the online time attack where you can compete against other players that can have you playing for hours to see who can break and exploit the game to the finish line the fastest.
The game is by all means worth the £6 but you're better off spending a bit more of that money to buy games like DuckTales Remastered and/or Sonic 4 Episode 2, despite them having lower scores on gaming review sites they're superior in everyway.