The Shadow SH075 kit was originally advertised as being as quick as any MIDI pickup can be - it takes 1.5 cycles to determine which note you're playing. Since that's as quick as physically possible, it tracks as quickly as any newer unit and is thus just as useful. I still haven't got round to hooking it up to anything except its own little floor-pedal synthesiser, the SH22, but since it's MIDI it can end up sounding like absolutely anything. Oddly enough, only one of my many guitars is the right shape for it - the Eccleshall Scimitar, which was designed to host it. But It does work on Telecasters and Les Pauls, which I don't have.