the bad thing about a stop n go is - obviously any flop is only going to hit any player roughly 33% of the time, so first villain gets 33% chance of hitting his hand (that's the good news). what this doesn't take into consideration is that villain can already have a pocket pair and if that is the case then villain would be pretty silly to fold to a 600 bet when pot is 900, he would be getting proper odds to call.

In summary, villain will hit his hand 33% of the time and if he has a pocket pair already he ain't foldin'. I think a push is right here. Even though you have little or no FE, it is outweighed by the fact that you need to accumulate chips to avoid busting out on the bubble and this looks like a good spot to double up, time is getting short with this SMALLISH stack.