If you mean the Radiotelephony Practical (rather than Theory) then that isn't one of the PPL exams. RT Theory is, but it is a written exam like the others. Anyway, at my flying school the instructors would recommend waiting until you have done some real navigation work and are ready for the cross-country qualifier before taking the RT Practical - that way you've had a chance to practice it and have something to relate CAP413 to.
Flight Simulators are, IMHO, almost useless for PPL training - there isn't sufficiently detailed scenery to practice VFR navigation and there is no substitute for the real thing for practicing basic handling (the lack of visual information also means that you spend too much time looking at the instruments to try and work out what the aircraft is doing). They are supposedly more use for practicing elements of instrument flying. At PPL level I think they're more likely to teach you bad habits than anything useful.
Last edited by Evo7; 20th May 2002 at 12:29.