Travis, the first few times I ran the tracks on my cable excavator I was disappointed with how easily they would lock up when dirt got in them but, after seeing most tracked equipment have problems with dirt in the tracks I realized these small models just don't have the mass to expel dirt out of the tracks when clogged. That being said though I am just careful running my cable excavator in dirt and only turn sharp on hard packed dirt.
It is harder to operate our miniature equipment in real dirt and that is a challenge that I really enjoy. But...I also enjoy moving rubber around all day and not stressing my equipment. The clean environment of rubber is nice too, I even have one tonka DT that I only haul rubber with.
So, I guess my point is that both rubber and real dirt can be fun and having equipment for each is a nice way to go.