Something I've not seen often mentioned on the forum but what's people's opinions and thoughts on the removal of the under bonnet shielding on their vehicles is it something that holds benefits e.g More engine sound? Aesthetics? Or is it a creater of problems? e.g heat and paint damage?

Some people cut holes in it to allow heat to travel to the wiper jets. I haven't heard of folk removing it entirely though 

You'll just hear the engine more and the car will feel less refined! The paint finish under the bonnet is not as good as on the top, some fords even being a matt colour in a quest to save money on lacquering places that don't need lacquering, so if you wanted to clean & 'show off' the underside it might need lacquering.

Why remove it anyway ?

The main purpose is to help smother an engine fire allowing the driver extra time to exit the vehicle. The tabs holding it in place will melt and the shield will drop and mould around the fire.
Some say it's to protect the lifespan of the paint on the bonnet. Some say it's sound. It's more than likely all those things.