Tampered glass is nothing but just some BS by those glass vendor.

Consider this,... Tampered glass has been around for ages....and why now? because the new gen house owner nowaday want "nice" look and not the prison look.....

You have 2 option: Take a risk to have no grill at all or do the conventional grill. If you dont want to prison look, forget wrought iron because it look too beng! and BTW wrought have the highest margin ratio so vendor love to sell wrought iron. secondly many kids and owner cut themselves with wrought iron.

if you go with minimalist design drill ie horizontal with thinner size ie 1cmx3cm instead of just square one like 1.5cmx1.5cm.

those window frame that accomodate 10mm thickness are not cheap.