(and countless hours in a loud John Deere tractor cab)
The guy I work for has a couple of John Deere 4710 800 gal 60ft boom sprayers and a couple of 4720 800 gal 90ft boom sprayers and those things are darn near as comfortable to drive as most new cars, GPS, A/C and bad-ass stereo systems ... much nicer and quieter than our spray planes.
I've never really listened for a difference with the grills on or off, can't remember the last time ours were off. The speakers do have a much more aggressive or meaner look to them grilless though, I believe.
