Thanks for all your effort martin!
I have a question, as can be seen there's a 0.4 GPM gap between the FuZion and the GTZ. Now, according to your flow estimator (), the following system:
FuZion V2
MCW60
2x MCR320 QP
D5
1x Res
6ft. 7/16" tubing
would yield 1.53 GPM. Let's replace the FuZion with a GTZ. 1.53-0.4 = 1.13 GPM.
Isn't it a big difference? I'm afraid 1.13 is not that good, esp. for future upgrades. What would be best for the above setup?

Thanks ^^