MrJimi,
Are you talking about the Makita 7 1/4 metal cutting saw? If you are they work great. I bought a Milwaukee for my father last year for father's day. He has cut 5/8" and 3/4" thick steel with no problem. I picked up some extra steel he had laying around a couple of weeks ago to start on some pallet forks. He sent the saw with me, since he wasn't using it for any projects right now. I am really impressed after using it. It is best to clamp down what you are cutting if it is not real heavy. There are almost no sparks, since they are kept inside the blade/ chip guard. There are cutouts to follow your marks on the steel. It is very easy to cut straight and stop where needed. I see Harbor Freight now sells one for $99.99 and so does Northern. Do a search on Amazon for metal cutting circular saws and you should have most of them pull up. I imagine the HB or Northern do not have as much power as this Milwaukee, but for the price would be nice to have around. The welding shops around here also carry them as do the Snap On man. I will attach a few pictures of some 1/4" I was cutting for a couple of brackets. The side (around 44") was cut and the notch. The 44" cut took approx 30 sec. Not much different than say cutting plywood with a circular saw. I have also cut quite a bit with a sawzall before and can be done nicely with some practice. You need to angle the saw back and use the correct teeth per inch for the steel you are using. You will still a fair amount of blades over time that could be put toward one of these metal cutting saws. Jigsaws are way too slow. If you are talking about just putting a metal cutting blade (like a chop saw) in a circular saw, it does not work great, like everyone mentioned. Lots of sparks and slow. You will also probably melt your blade guard if it is not metal.
Good luck,
Russ
