Speaking as someone who is experienced with woodworking and power tools, the mighty-mite saw looks dangerous. The small footprint and tiny fence would make it difficult to cut track safely. Also, I don't think the diamond blade will work well for the non-metal parts of a piece of track.
If you have a few pieces to cut, use a hacksaw or a dremel (make a few practice cuts). If you have a lot, look into a metal-cutting band saw or a metal cut-off saw - you'll spend more money, but you'll work more safely and save a ton of frustration.
I buy some stuff at Harbor Freight (very selectively), but their power tools are false economy.
