Ok I will probably attract a lot of flames but here goes:
I think Callaham block is hype. I have played strats with reissue tremolo unit (with steel block) and callaham units and honestly I can't tell the difference. Some of the differences like machined bevel and extended string hole is purely functional but from a tone perspective I just could not tell the difference. I have a guitar that has the Wilkinson VS-100 which has zinc block and it doesn't sound bad either. I seem to get more sustain that I can tell by turning the volume of my amp up. Also I get better tone variation from different amps and pickup and strings.
Furthermore I don't like the whammy bar that the callaham unit comes with... they sit too close to the body and I cant grab it without hitting a volume or tone control.
If you want tuning stability with tremolo either use wilkinson or floyds.
I think Callaham block is hype. I have played strats with reissue tremolo unit (with steel block) and callaham units and honestly I can't tell the difference. Some of the differences like machined bevel and extended string hole is purely functional but from a tone perspective I just could not tell the difference. I have a guitar that has the Wilkinson VS-100 which has zinc block and it doesn't sound bad either. I seem to get more sustain that I can tell by turning the volume of my amp up. Also I get better tone variation from different amps and pickup and strings.
Furthermore I don't like the whammy bar that the callaham unit comes with... they sit too close to the body and I cant grab it without hitting a volume or tone control.
If you want tuning stability with tremolo either use wilkinson or floyds.