How many hands before opponents stats are reliable?

[kidcolin]

Hi guys. My first post here. I just started datamining and using PAHud. So far I'm digging it, but I'm not sure when I can "count" on the stats. I mostly just use it to consider preflop decisions.

Tonight, though, I noticed a few times guys with a 10-12% PFR after 350-600 hands opening, and then seeing them showdown junk, like J9o or A4s. Threw me a little bit.

I know it takes a long time for stats to converge, but how many do you think is a good number on average?