Your total investment was 10+20+40+80=150
You won 248 - 150 = +98.
You can play system with odds @2.00 and more but system I'm talking about min. odds is @3.00 so what follows is only one type and it is X where the minimum odds @3.00.
I have a friend who played the system,
he start with 10Euro and stakes have gone up over 100euro and bet win (is not trying again).
The system did risky, but how to play a good match probability is increasing...
The chance to get long red streaks will be higher with odds @3.00. This system won't work if someday we found a very bad luck and we unable to win after some tries. We may run out of money to chase our previous loss or we may encounter a max profit feature that the casino applies which will halt us to make the next bet. Indeed martingale could give us profit but if we keep using it for a long period of time then we will meet the bad situation and we unable to handle it in the good ways.