they are annoying, frustrating, and that little beep or click will drive you mad, but it's worth it.
get one, set it on about 84...and practise your favourite scale...for me...i like A harmonic minor, D phyrgian, E phyrgian and E melodic minor, 2 octaves ascending and decending...and play it.
start at one note per beat, or crotchets. once you can do this perfectly...move up to 8th notes...or 2 notes per beat. once you can do this well, (i normally do it until i play it through 3 times perfectly before moving on) keep increasing the note divistions...go to 16th notes, then 32nd beats.
84 might seem very slow when practising 1/4 notes, but it gets fast very quickly. once you can play one of these scales at 32nd notes at 84BPM...move it up 20 beats per minute or so, and start with 1/4 notes again.
this is VERY frustrating...especially once you start getting past 120...but it'll help your playing so much you won't believe.
for me...i'm trying to hit 32nd notes at 180...though it's pretty goaway. the most important thing is that you play this CLEANLY!!! sloppy playing, not matter how fast, never sounds very good. practise this clean...ie, no distortion, no reverb, chorus, delay, or any other effects. it'll help, believe me.
