Pepsi Max > Pepsi > CocaCola > any other 'cola'
Also, 'cos it's slightly relevant, Pepsi (cherry) > Dr Pepper > Cherry coke.
I can taste the difference (I find it bizarre how some people can't, tbh..) and I've always preferred Pepsi. Probably 'cos my Dad prefers it so that's what he always bought while I was a kid..