My opinion is both are the same so I don't think you will get better separation using one over the other. Using either ferrous or conduct, all you are getting is how the machine will report the signals it gets.
I think ferrous is easier for some because it gives low tones for signals on the left side of the screen while conduct gives tones based on relative conductivity of an object detected.
Using conduct in iron infested areas can be a challenge because nails can cause iron chirps that have to distinguished from high conductors, such as quarters, dimes and pennies.
IF one uses any iron mask while running ferrous sounds, it will not separate any better than using conduct with the same iron mask settings, only using one or the other will be reported differently.
Many ferrous sound users run without any iron mask and claim it will separate better than using some form of discrimination.
There is a large number of successful users that use ferrous or the conduct and find good stuff in iron ridden areas, even with varying degrees of discrimination.
The same can be said of using auto or manual sensitivity. The key is to find what works best for each individual user.
I started out using conduct sounds and after time tried ferrous. I can see how it could make telling nail chirps from high conductive coins for some but I got real good using conduct and didn't want to run ferrous and stuck with conduct.
Some even use both settings, ferrous and conduct under different conditions, like using conduct where there is modern trash to deal with and then using ferrous in old places where there is little modern trash.
To add to the above, a few like me use conduct sounds along with audio 1, which gives a signal as long as the coil is over an object. I think this helps me find the weak good signals and allows me to analyze most of those iron chirps and ignore them or pick out a non-ferrous item mixed in with iron trash.
I guess what I am trying to point out is there are a lot of different settings that are used successfull by various users, don't be afraid to experiment and see what works for you best especially after you get some time getting to know the detector.
If you are using bryce's other settings, I would stick with conduct sounds, I think that is what he uses but this is JMO.
Hope this helps,
HH