I like the grilles over windows in current house
We were burgled 2010, Phuket, helpful Chalong cop showed how the aluminium joinery windows could be popped out in seconds with a small pocket knife
Spent three years in previous 2 storey house with same style alu joinery (could leave upstairs windows open when out), but house owners on same site and no problems
Current house, grilles. Single level, windows open almost permanently, mosquito grilles too, safe/secure, esp last year when I've started working out of the country for MsH/daughter at home, have long-term vacant houses each side no immediate neighbours
I would fit them if our own house.