My favorite is Liquid Ebony, I haven't seen it in ages but would buy some right now if I could find it.
I've tried various methods and products it's almost silly.
My results have found the best product for me is Meguiar's G17216 Ultimate Compound. If you're confident with a true buffer that's the fastest route, but also the fastest way to damage your paint if you're not on it.
The porter cable random buffer or equivalent is what I recommend for touch up work and newbs. Much less risk of making mistakes and still performs reasonably. It's a good compromise in speed and forgiveness.
I am in no way advertising or affiliated to the product. Just a hobbiest.