25 and 30NL are the highest I play currently, I also play 20NL, 16NL and sometime even 10NL. It depends on how good the games are. Sometimes at 25NL it can be hard to find a good table, and I move down if the action looks better. Not sure when I first started playing 25NL maybe 4 or 5 months ago , i only have about 25k hands at the stake.
I have 1k+ hands on a number of villains but not even close to 1 million hands in total, it's just that I see the same regs so often as I am multitabling and so are they and playing 9 handed tables.