Hello Corey, I have had one for close to 8 years on the Silver and red 93. While it is a single pass, not a double pass. I feel it has help and I have not had any issues with it in the super cold weather up at my house. I do feel that the summer time performance and the extra capacity in the system adds longivity to the ATF fluid when heavy off roading. I do think the initial bleeding can be a pain, getting all the air out to totally fill the system. I had to angle the out let a bit to allow full filling.
Anyhow, just my 2Cents.