I don't have any Danelectro pedals, but since no-one else has replied, I can try to explain one of the features you mention. Cheap pedals simply 'turn down' the effect when you swith them OFF. There is often a little bit of the effect still present in the output signal even when you don't want it. A feature that some manufacturers call 'true bypass', uses a switch to route the signal straight from the IN jack to the OUT jack, so there is no residual effect leaking into the signal.