This isn't really Mountain West weather, but this is my first side-by-side comparison of Radarscope vs. GRLevel3. I decided to buy Radarscope. It has several nice features.
There are definitely a few things that are different, but Radarscope has the super-resolution (Level-2) reflectivity. It has super-resolution (Level-2) base velocity, but I don't see storm relative velocity. So I guess I will still have to use GRLevel3's storm-relative velocity for some purposes, which is nearly at super-resolution.
They have the same features for composite reflectivity. They have pretty similar features on the dual-polarization fields. GRLevel3 has better resolution on 1-hour rainfall and VIL.
Radarscope has a distance measurement feature that makes a circle, showing miles. GRLevel3 has markers for measurement, and you get nautical miles. It's kind of funny that sometimes the maps show different small towns, but that's just the difference in the built-in maps from some national database.
Storm tracks are a little different for some reason. Generally, I don't like the storm tracks, so I turn those off when I use GRLevel3. I pretty much just use hail icons in GRLevel3. Nice green hail icons make you think that every storm is throwing out 1"-2" hailstones 100% of the time. That's fun!
GRLevel3 is more customizeable in terms of which types of warnings to show, which types of storm information to show (hail, meso, TVS), storm reports, and ability to load specialized color schemes. Radarscope has built-in support for MPING (cell-phone app where observers report any precipitation type, or possibly severe weather). I haven't found any severe storm report button (NWS).