By best, I mean good in any way like reliability, speed, convenience.
Sometimes an escrow may be the best way.
But then there are OTC markets.
They don't seem to show up on coinmarketcaps. (they do have rankings for exchanges)
And "easy to find" is another "good" thing about them.
Binance all fits your criteria: reliability, speed, convenience.
You only need Level1 KYC if you are trading less than 2 BTC.
And level 1 doesn't require any documentation from the user.
This is great if true. Thanks.