i understand the frustration.
can you explain something? the firearm is in the same place relative to your face, whether you are left handed or right handed no? shouldn't the spent shell casing still pass by your face on the right side independent on whatever hand you are shooting with?
sorry, as a righty, i don't understand and mean no disrespect (intentional or implied) whatsoever to the left hand population. this forum has been on a hair-trigger lately, it needed to be said. 
maybe i'll try a few left handed shots to see it for myself.