Throttle stops.. Some one help me :)

[Super73]

Ok, I know nothing about them. Looked at summit and I see there are electric and CO2 based. What all do you need to make them work. Here is what I'm looking for.

Set initial starting throttle by %
Set a time frame in which it will go wide open

I'm finding a few more events by us that are 1/8 mile no track prep. I want to be able to set the throttle stop at say 40% while holding down the trans brake button (this is new to me too). When I release, it goes WOT over say 1 second or so. I think it's be easier then training my right foot

I think I like the idea of an electric so I don't have to fill another bottle. But not sure.