What's legal nowadays? Can i use this stuff or will it be too sharp?

Black mesh

Don't know about IVAproofness, but it's rubbish as a grill. It has a lot more ally than holes and really restricts air flow. You're much better off with woven stainless mesh (and it's IVA safe) than expanded ally mesh.

I second that. Had that on my grille and was plagued with cooling problems for three years until I tried removing it and then ll of a sudden everything was fine! From an airflow point of view you couldn't really design worse.

It should be ok for IVA though.

I used the aluminium mesh for SVA and it was fine but as has been mentioned, it's not the most efficient for airflow.

Here is the stuff you want:

http://www.lockwoodinternational.co.uk/stainless-steel-grille-mesh-c483.html

I'm planning to get some to replace my aluminium grille.

Cheers,
Craig.