I have switched some times between paper based system Time/System (Design), Filofax Professional System and Palm, Ipaq. Because this item about from wich system you get the best result pops up from time to time I think it would be intresting to hear more experince from what is best. Now many will say the system is not so important, it is the metod GTD or anything else wich matter.
But please leave that for a moment and concentrate on from wich system do You get most benefits and result, paper based or PDA ???