Stratton can do OK in upslope, I really don't think they are on the same level as Woodford and Glastenbury. Stratton will struggle a little more in blocked flow upslope while Glastenbury/Woodford clean up, they also clean up unblocked as well. I've been up there a few times after upslope events and never seems like "wow, they got crushed". Synoptic storms, yes, they do really well normally as would be expected.
Interesting about the snow making contamination-could be a factor.
Here is an example of the Nov 2016 upslope storm I was talking about. This was purely upslope IIRC, but also a very blocked flow one too I believe. Woodford had 26", Stratton area 9" looking at that map. (ALY has the Woodford area shaded too far east on the map--they always do for some reason-so bump that really dark shading over west a bit.)