It seems pretty much confirmed we can see Ethereum going under $400 these days.
Qn - Is it a good buy under $400 or wait for even more price drop?
I think the price of ETH will down to 350$ and will increase again
But it depend on you if you want to buy it and after that just hold it until the price recovered
I know there is no trick to know whether its good to be deeper or not because i have some etherium but also i want to buy deeper.
However, good or not is not the matter because nobody will noticed this to make profit but try to buy at lowest price possible bring much more chance to make money.