Often times we aren't shown the procedures that products go through to test their limits and prove that they are safe. This is especially true when it comes to motorcycles, as opposed to the testing that automobiles go through.
This video compilation shows a number of different testing methods that are used by BMW to test their equipment. The tests span crash testing, neck brace testing, water resistance, and tear resistance. It's quite interesting to see these different testing regimens carried out as a behind the scenes look at the development of BMW Motorrad equipment.
There is no commentary or explanation to go with the video however, and this leaves it up to the viewer to figure out exactly what they are looking at. Adding some type of narration to explain what is going on in the video would make this an substantially better piece of content, in my opinion.
None, I just walked in there and bought whatever fits and I think is protective. Doesn't mean I'll go in there and buy something from an unknown brand, something tried and true and the employees at the store is very knowledgeable.
As long as you're buying from well known brands you're basically in the clear, they can't only get so bad. And when you're buying something from BMW for example... there's almost no question as to the safety of their equipment.
BMW motorrad products may be safe but I find them overpriced compared to what I can get at the bike store when they're having a sale. I'm sure BMW products are great but so is suomy, shoei and a plethora of other brands out there.
Your chin and everything not covered by the helmet is fair game for the asphalt. realistically, you won't always land right where the helmet covers.
Modular helmets aren't the safest either because a hard impact can flip the front plate up and leave your face open to injury.