Most think the snow thrower (single stage) is best for slushy (wet) snow. My experience is along these lines, but you don't say your two stage snow blower plugs up - but just pushes snow. May be something about the design that does not let the snow into the auger that feeds the blower. With belt driven blowers, mistakenly twisting the belt wrong will make it run backwards, which cannot be your problem. Just that the results are the similar.