SMD Stencil Material Choice
The assembly house I used to rely on once told me that the stainless steel ones are more durable, and that makes sense as steel is a tougher material compared to bronze.

I wouldn't worry too much about the laser cutting, as the stencils are polished, which will remore any sharp edges.

If in doubt ask the manufacturer for clarification, but in my opinion, saving $35+VAT is not worth the hassle of having to redo the stencil, and fix badly soldered boards at a later date, when the stencil it worn out.