My initial reaction was "well, it's your car, if you like the idea then go for it" because providing you keep the cut-out sections somewhere you can always glass them back in if you decided it wasn't so good.
My second thought was boringly practical..... is that going to let water into the ignition system ?
The OEM vents are fine mesh and let hot air out but from what I can see, not much rain down onto the engine. The S1 Elise has grilles in the middle of the rear deck in about the same position as shown but they are a much larger mesh and certainly let water into the engine and cause misfiring if you're stationary in heavy rain. (yep, got the T-shirt)
The MR2 also had a large grille section over the engine, but the clever Japanese had decided to put a drip-tray underneath to channel any water away, and that works very well.
Brian
