The addition of Toe Down and Heel Down messages to the expression presets is very powerful. I am using the MC6 and a Dunlop Mini(X) expression pedal with a HX Stomp to achieve the same functionality as the Mission SP1-L6H expression pedal.
The SP1-L6H has an expression toe switch that allows you to switch effects on an off directly from the expression pedal. You can turn your wah, whammy or other effects, on and off without having to take your foot off the pedal.
The SP1-L6H only works with the Helix Rack, Rack floor controller, and HX Stomp whereas using the Toe and Heel commands on the MC6 allows you to use it with any Helix product.
An enhancement to the Toe Down and Heel Down messages which would be really useful would be to have the ability to designate a message as Pos:1, Pos:2 and Pos:Both and in doing so allow the Toe and Heel messages to toggle. Using Pos:1 and Pos:2 messages would in effect allow the MC6 to functionally emulate a switch. In fact 2 switches. One in the Toe position and one in the Heel position.
One of the main reasons I think this would be useful is because currently one has to remember which messages (intended function) are associated with the Toe position and which with the Heel position. And in reality the desire is to be able to turn some things on and off with one physical action, i.e. have the action serve as a toggle switch.
Another advantage of being able to toggle the messages on Toe and Heel is that often being able to start the pedal movement in one direction rather than another is preferable. For example when toggling between volume pedal and wah blocks on the HX Stomp I would prefer to sweep up from minimum to maximum expression rather than down from maximum to minimum. And if the Heel position could be toggled it would be possible to do that. Again this is something the Mission SP1-L6H won’t allow for.