Anyone with experience or knowledge please shed some light.

I have Bride zeta's

From what I understand you can use

FO - type rails and FG - type rails

I understand one is suppose to sit you much lower. At the cost of losing easily access to that lever to make your seat move .

Does anyone know exactly how much lower it is ?
Also the FO - type rails look alot more durable since they have a cross bars from rail to rail.

Im 6'2 so a lower rail is nice however if its really not that much lower , to me atleast its not really worth it to lose easy access to moving my seat back and forth.

So does anyone have experience with both rails? Is one much lower or more durable then the other?