For a circular saw I’d go with a worm drive. Can’t say which model would be best. I’ve used a Milwaukie and own the Makita. I’d say they are fairly equal. But yeah, if doing a lot of work with a circ saw a track saw would be the way to go. But one thing you mentioned about the magnifying glass… make spacers for laying out stuff like that. Have a pair for each side of the shoe that is perfect and then you just place the spacers on your mark, clamp your straight edge and away you go

Angellos