The circuit protection starts at the circuit breaker panel which controls the maximum amount of current allowed on the line. The National Electrical Code is followed by municipalities to make sure the proper wiring and circuit breakers are used. All Task Lighting Angled Power Strips are internally wired with12 gauge wire which is rated for 20A circuits. With this in mind, you can have a 15 or 20 amp outlet in the strips. It is the total amperage drawn that is being used from the power strip, and if more is drawn like plugging in two toasters and a microwave, if the current exceeds the circuit breaker limit the circuit breaker will trip. This protects the power strip.
The deciding factor on which Angled Power Strip to use depends upon what appliance will be plugged into the strip and the styles preferred. If the appliances are 20 amp rated they will have a "T" plug, not the two Plugins. With this known, the overriding factor could be the building department requirements in the area.