You're welcome, Saboin :)
Until last week I have had screw-on filters (CPL - Circular Polarizers and ND filters from ND8 to ND1000), but especially when you have a bright sky and a darker foreground you might need a gradient ND filter. This is the main reason, why I switched from screw-on filters to such a system.
To be honest, I do not really care about the white balance when I'm shooting, because with digital photography it's not really neccessary, as you say ;)