I haven't tried Start8 for quite a while. There wouldn't be a positive answer too your question.
I don't think either is "better", just a difference in the layout. Classic is (IMO) totally customisable, so , without using the other, I am a little sceptical regarding Start8 having more options?
Speed? When I start from cold, without using any electronic timing mechanism, Classic goes fairly instantly to the desktop, there could be a pause of a fraction of a second, however. transiting between the modern and the legacy desktop, it is, to all intents and purposes, instant.