Taking shots vs moving up

I play at Ultimate Bet and have done pretty well at the .5/1 ring games playing both full and six max. After 25K hands, my winrate is at 3bb/100 exactly. But due to some transfers to a friend, my roll is sitting at $400. I occasionally take shots at the 1/2 level, but keep losing and returning to my usual limit. My question is: Do people find it easier to get fully rolled for the next limit, ie wait for $600, or to take say a 25 or 50 bb shot and if you do well stay at the limit? I guess this question essentially turns into a poll on how you got to the limit you play.