Minihobbies valves are all I use and they bleed the air so you can open that hatch when power is turned off. I've found this to be helpful in any number of ways including the speed brake on my Euro Sport with my switches and fills etc. I show up to the field and I can open close it without any air on board, then when I park after a flight, I turn the airplane off, and I can close the speed brake

Todd uses another brand that does the same thing, don't remember the name though.