I purchased this to replace the steel block on a Wilkinson WVP6-SB trem.  It fit very well and has a bit of heft to it (it weighed 10.6oz as compared to the WVP6-SB block at 6.9oz).  The only reason I subtracted a star is the string holes are not drilled as deeply as the stock Wilkinson block, by about 1/4" or so.  This seems to affect the tuning stability a bit, but not too much.  Other than that I am very pleased, and a quick trip to the drill press will fix the one thing I don't like about the block.  The block made a significant improvement in the tone of the trem, with more sustain and heft to the tone.