That’s the game completed with Tails and all the Chaos Emeralds now. During the process of doing this I also managed to get all the Gold medals on the Blue Spheres bonus levels.
Which means the only thing I have left is a run through with Sonic and Tails together! Not really looking forward to that. Tails on his own is tolerable, but when he’s following Sonic round he has a tendency to kill you.