i think my record for expert is around 250-280.
The only thing sucky about minesweeper is when you get to the end and you have two 50/50 situations. There's no way you can tell where the bomb is. So it's like, 25% chance to win, even if you did all the work to clear rest of it.
The only way I can deal with it is fail two dozen games by clicking the 4 corners; waiting for that game that has less of a chance of 50/50's.