Sierra = Honda.
I used to live near Tahoe and my 20-year-old HS80 took everything thrown at it which was quite a lot. I have since moved to Maine and bought a newer larger HS928 but the HS80 is still serving duty as a backup and it's been dang good at it.
Tracked Hondas are specifically designed for serious snow conditions. They can be difficult to maneuver in areas with mild winters and frequent snowfall/melt cycles throughout the cold season and in fact I noticed that a majority of people who complain about their tracked Hondas on the Net happen to be using them in conditions where such a machine is overkill or even completely inappropriate. Apparently some people have difficulty grasping the concept that on pavement or gravel wheels work better than tracks since they offer much less resistance and friction but this is done at the expense of traction, obviously. That's the reason why when it comes to areas with months-long snow cover and ice/packed snow base wheels are no match for tracks, not even close. Tracks will keep on providing traction in conditions where using a wheeled blower turns into a skid-push-pull-curse fest.
In such conditions the Honda's fixed axles are an asset rather than an annoyance, providing even traction for years whereas many blowers with unlockable axle have a tendency to develop a pull on one side under intensive usage because operators tend to always lock the same side causing uneven wear patterns. In deep snow tracks perform better than wheels regardless of base because they can ride on top of the deepest layer without sinking much meaning you can clear snow via multiple passes vertically as well as horizontally. This also allows clearing "old growth" hardened snow regardless of depth or how long it's been laying there, however this requires some patience, but it can be done.
The best is yet to come. By "8 hp tracked newer Honda" I am assuming you mean the HS828 and not the older HS80. Like all newer Honda blowers rated 7hp and above the HS828 comes with deep snow's worst enemy: the hydrostatic transmission. This means it has no fixed gear speed ratios, instead it has an infinitely variable speed control both in forward and reverse. Tackling deep snow at too high a speed can overwhelm the engine of even large snowblowers and with some really serious snow even the first gear can be too fast. Honda's hydro tranny allows to operator to set the speed as slow as he/she wishes, down to a few inches a minute. Doing this I am able to deal with even the nastiest EOD mess at a pace that allows the machine to get the job done without bogging down and/or imposing undue stress to the engine. In these snowy climes, short of a 30hp utility tractor II can't imagine using any other blower than a Honda.