Manual valve body in street driving?

Yeah my 7 1/4 is getting deep-sixed for sure, probably going to go with an 8 1/4. And I'm looking at a 2200-2500 stall converter from SMR Trans. I chose the valve body with part no. 17675 because on Turbo Action's website it says it allows full engine braking in all gears, not just 2nd and 3rd. I want this feature because I intend to road race the car more than drag race and for that engine braking is definitely a plus.

EDIT: Oh and I'm thinking of either 2.94 or 3.23 gears with the A-999 low gear set. Anybody know where I could find that gear set BTW?