im just trying to do extended shallow dives. I will be taking photos underwater and as you know sometimes you have to wait a good deal of time before your subject cooperates for the perfect shot. this is why I want to use doubles but it is not possible for me to bring a real doubles set up. I will be renting tanks , this is the reason why I want this "suicide or cheater device."Putting 2 regs on 2 tanks is going to take less 'fooling around' than this manifold setup you're talking about
According to your profile you have a Nomad sidemount rig so why not use that with independant doubles
Doubles with only 1 first stage is limiting your redundancy
What type of dives are you planning on doing?
thanks for the input and I appreciate all the advice. you guys are great...
Mike H