Don't drill holes in your bonnet...you'll reget it!
why do you say that?
Well if you want to get rid of them after they have been on the bonnet, they will leave 2 or 3 visible holes in it, which will have to be patched up if you want to go back to the smaller bonnet vents (which look better IMHO)
I also think its a waste when a bonnet with the holes already in it are possible to get.