You have to use what works for you. The Gibbons-style plectrum harmonics are another completely different way of getting harmonics.
I mostly use "natural" or classical-style harp harmonics: pinching the string between r.h. thumb and index - the index picks the note the thumb hits the harmonic node point. What I've found is that I can get a lot of different harmonics with this technique (especially on electric with some drive) - basically any point on the string will throw out a harmonic and on first and second strings I can even get ultrasonic harmonics (a few cm from the bridge).
Listen to the lead part in this (0:35 on) - it's mostly harp harmonics:
http://ratcliffe.co.za/music/a_alan_blue_spy.mp3