My company has bought hundreds of them. If we order a porta band we have to have good reason. The metal saws cut anything and are much faster. I haven't used a hacksaw in years either. You do need to wear eye protection with them because they do through some metal around even with the blade guard.
We have found that they don't do well with stainless strut so we have gone back to the porta bands for that. The stainless metal eats up the blades pretty quick.