The German motorcycle magazine MOTORRAD NEWS performed in impact test with 12 protector inserts. I would not translate the entire test here. But as a quick buying guide for some it may be useful to know which protectors came out as the best:
3. 2WD SC1
Impact remaining from a 50 kN impact: Knee protector 16 kN, Hip protector 20 kN
Safety: 5 points
Comfort: 4 points
Price/Performance: 4 points
Price for 1 piece: Euro 12.90 - 19.90
Summary: With top results for the impact tests and ergonomically purposeful design earns it the full 5 points for safety. Great flexibility, thus this product is comfortable to wear, too. Only point to note is the size of the knee protectors is very big.
2. Louis Pro Safe 98
Impact remaining from a 50 kN impact: Knee protector 19 kN, Hip protector 21 kN
Safety: 4 points
Comfort: 4 points
Price/Performance: 5 points
Price for 1 piece: Euro 7.95 - 9.95
Summary: Our price-tip! Reasonable protection for a low price! These protectors do wear pleasantly, the knee protector even has aeration holes. The dampening results could be somewhat better.
1. BMW NP Protector
Impact remaining from a 50 kN impact: Knee protector 11 kN, Hip protector 13 kN
Safety: 5 points
Comfort: 4 points
Price/Performance: 5 points
Price for 1 piece: Euro 16.00 - 20.00
Summary: Class-leading impact results, individual shape for every protector, aeration holes on all protectors, great flexibility and generous size make this product to the best in terms of safety and comfort. Problem: The expensive protectors are designed for BMW motorcycle clothing and may not fit into other brands pockets.