There's an article in the new Travel & Leisure discussing the value of First Class amenity kits. Here's an estimated value of T+L's favorites (calculated on the per-ounce price)...

AIR FRANCE
Estimated value: $49

EMIRATES AIRLINES
Estimated value: $79

SINGAPORE AIRLINES
Estimated value: $85

LUFTHANSA
Estimated value: $72

JAPAN AIRLINES
Estimated value: $137

SWISS
Estimated value: $83

CATHAY PACIFIC
Estimated value: $123

MALAYSIA AIRLINES
Estimated value: $62

ASIANA AIRLINES
Estimated value: $72