From what I understand from lethal is its more cost effective for the consumer to build a dead head kit vs normal return due to less hoses, fittings, etc. They run them on their builds without issue i just think it comes down to more of a personal choice.
IMO it depends on the demands of the system. If someone isn't running that much power or the pump aren't big pumps, then doing a dead head setup is fine. Bigger pumps, more power, using a y-block and feeding the rails first is the way to go.
A setup I am doing right now, which he is only using gss342 pumps and running 500hp...
-8 feed to the regulator, other side of regulator to front of driver rail, crossover in the back and plug the front passenger rail. Return from bottom of reg.
And frankly, there is no need for -10an line. We do not run enough power that would require a line that size.
Well my goal is to be at 800rwhp I don't want to be changing things around,that's why I'm waiting to find out what's the best way to run