That depends on what you are using the ratings for. If you are trying to use the ratings to know if your team should have won thegame or not, then they might be useless. If you are using the ratings to get an overall generalized picture of your team's efficiency in various areas of the GE based upon the skill ratings of each player's contributions to each area dependent on his minutes played, then they are spot on.
Maybe you ought to read the whole thread.
Once I scored a basket that still makes me laugh.