I'm no expert, but I am observant. I've seen pics of the B&M, TWM and Pacesetter shifters. I chose the Kartboy for price and coz I like the cool logo. ;-)
Pacesetter is the most expensive and has what looks to be a poly ball that adjusts up and down on a treaded shaft. About $170
B&M and the TWM are about the same. Only diff I could see was that the TWM has a longer shaft under the pivot ball, so they have to include heat sheild spacers so your shifter won't rub. TWM $122 B&M $135.
Kartboy shifter does not rub the sheild, the clearance is just right. The shaft is steel just like, I believe, all the rest. The main difference between the KB and the B&M/TWM is that the pivot ball is machined aluminum and is fixed to the shaft. Price for the KB shifter is $90, but the super combo (shifter/trans-side bushing and oh-so cool knob) is a steal at $130
Does all this sound right Tom?