The problem with your question is that if you've used a progression, it's impossible to answer you specifically. If you bring things back to ½ probability calculation (like EC), you have 600/5 = 120 units (in flat bet on EC).

Personally, I have already met + 351 units (not counting zero) in flat bet on EC and finally, the method was losing! Few players would think that we can return 350 units won in flat bet (I also thought spontaneously before thinking back to the probabilities) but, as the dispersion on EC is almost 1 STD on average, sooner or later (here on average 120 000 spins, without the zero), we meet a movement of the game as ample. It is up to you to convert this STD value according to your type of bet (5 numbers on average or other type). Your certainty of winning will be in your % profit well above 1 STD (in time) because 1 STD + zeros.