I know Ron's cars are as accurate a copy of a real Diablo Roadster as you can get.
When I drive my car, needless to say, it always gets a lot of attention and questions. This is the 7th replica car I have owned in the past 40 years. I currently have two, and this one is by far my favorite. I never try to fool anyone, telling them my cars are the real thing. I always describe them as replicas and go into the details, to give credit to these amazing crafters and builders who make them.
Because of this, my personal opinion is that I don't really need the V-12 cover. My car has a 3.8 Supercharged engine in it, which is more than potent enough for me. I've taken the original motor cover, painted & badged it, and I'm going to have the lexan window installed on the bonnet, which I just like the look of, and apparently many others do also, as evidenced by even the new mid-engine Corvette doing the same thing.
I also know that engine cooling is determined by engine design, Radiators and cooling system efficiency, but Lamborghini paid Engineers a lot of money to design the body and air intakes to help cool the engine compartment, and I feel putting a full cover over the engine kind of defeats that. It's like layering clothes in the winter.
In closing, I'd just like to mention that in the year and a half I have owned this car (Purchased in very poor condition as a result of a theft), Ron Dolling has been extremely helpful. I have purchased several items from him and he has been way more than generous with his time, giving me tips, clues and even sending me pictures and printed instructions. He will even call me back to find out if I was able to solve a problem.
As far as I'm concerned, Ron Rocks!