I use the $7 Harbor Freight tool with those thin cut-off discs daily. If I am careful, I can also drill teeny holes with the thing for handrails.
There is no other tool around here that can cut cab windows in .020 brass. I did have the $60 Sears model with better speed control, but it died.
One has to be careful with Harbor Freight, but some of their tools are truly spectacular bargains. This and the small cast iron drill press are essential tools for a hobbyist or aircraft restorer. I have had lousy luck with their spray guns and bench sanders, but these two I depend on!