The idea here is to catch the oil/parts in the event of an engine failure. Last thing you want is your rear tires getting soaked with oil and losing control which is what happened to Mike Smith. They also have a Kevlar version available.
As to ease of install..... dunno. Haven't gotten mine yet to install it Keoni.
Car can still be DD'd with it. It will retain some heat with it though. It is after all a blanket. There are quick release type connectors so it should be easily removable. I think the hardest part about it will be setting up the straps the first time to get it fit correctly. After that, it should be a simple unsnap when you don't want to use it.
Again..... I have not seen mine yet but it was shipped to me today. We will have more answers hopefully by the end of the week or this weekend.