Your link to the saws is a bit outdated, here is a great deal on a modern cordless metal cutting circular saws that is made for this stuff:

store.evolutionpowertools.com/products/s210ccs?va…

And if you want to be a big shot:

www.acehardware.com/departments/tools/…/F012588?s…

These units are more powerful, faster, and designed for cutting a variety of metals you may encounter on the streets. They also collect chips so the risk of them getting in your clothes as evidence against you is reduced.