At 150k hands of full limit in the micros I just came to the conclusion that I am a winning player and that I won't bust out with 300 bb 99 times out of 100. I will however do it once.
I have in my 150k hands at full ring had 1 450 bb swing down.
Technically, there is a formula you can use to determine what personal bankroll should keep you afloat.
http://support3.com/poker/bankroll/bankroll.asp
You need to know you winrate and standard deviation for this one but there is another one using thresholds that is more accurate, which ranges your winrate.
In other words it will help you know if you have enough hands to determine if you are indeed a winning player.
The other problem is moving up and playing 6max vs full ring, which essentially should be a new calculation.
Currently I have 10k hands at 1/2 6 max and am down 100 bb so no bankroll is going to keep me playing there but at the limit lower I probably could play forever with a 300 bb bankroll.
And of course that also means I don't get worse or my opponents don't get better, which is not likely given the enviroment of the day.
I used to be a 10 handicap golfer when I was 13 but I doubt I could break 90 today.
Just keep on working on playing well, pick tables that you can beat and eventually you will find more and more tables to pick from.
Table selection is a critical skillset that is underutilized in the micro stakes world. It is at least worth 2 bb/100 in my opinion.