Nothing under 200K for 6m, a lot less for HU (presuming you generally play the same number of each "player type"), maybe 50K. If you're having a 4 tabling dick swinging contest with another reg that is at approximately your same skill level, maybe 100K to get a much better idea.
Impossible to know in 6-max games. By the time you get enough of a sample size for either one (I think 500k for a solid ballpark estimate, 4 million for something pretty accurate) your own game will have changed significantly, and the conditions in the games you play in will have changed significantly. This assuming you fall somewhere in the range between a really good reg and a small loser. If you're a total monster that absolutely soul crushes everyone around you or a massive fish, you can get more accurate information quite a bit quicker.
Thanks for the input guys. Ive just begun to really grind plo fulltime, finallt made the switch from sngs. And just want to knowmore about swings, winrates, sample sizes, normal below/above ev etc...
