GE definitely makes a big difference on arrival, just as you too experience.
But here is what I'm observing:
The variance with wait times to deal with the CBP passport control step is increasingly worse with GE for my TATL flights, while that for the "unwashed masses" crowd on SAS TATL flights is in a more steady state of remaining with much worse average wait times than GE but the variance in wait times for these "unwashed masses" being just about as bad as they were before CBP went with this Simplified (Biometric) Arrival stuff for so many US airports of entry for SAS TATL flights.
Even if things were different with wait times, I would still generally prefer to do an international transit in AMS, CDG or even Germany to get to a destination outside of the US than to transit the US to get to a non-US destination, but SAS can't realistically be expected to do anything about that.