I prefer my step bits to hole saws for sheet metal. The opening is cleaner and more consistent. I do need to get myself some larger step bits though!!!
The biggest problem were the grommets I have... The larger ones have a very thick wall so I settled for the one that just fit... All in all, it is probably better this way... The cables fit perfectly with little to no wiggle room.
I was thinking about adding some ventilation holes to my rig... Using my .22 or 30-30...:banghead: