they both modify a stock shifter. the results should be essentially the same from either vendor. i believe that silvertwin has been know to make them even shorter than is common for members who request it (due to aftermarket shift knobs that mount higher than stock).
flip a coin.
"The two seater is being joined in a few weeks by a larger two-plus-two model with a rear seat for munchkins." ~Jim Mateja, Chicago Tribune, in regards to the Z32.
Andrew Janeshek // jnshk@aol.com // 1992 NA 2+2 [Stage 2-ish]