nothing, John is a great guy, he will replace the ferrite for free, you pay for the black end plates and you can get free custom engraving with every order.
mine went from portugal to the US and back in less than 2 weeks, amazing service and super quick. also the work is top notch, i highly reccomend JDS Labs.
yea I liked the cMoy Bb i got from them, you think he would replace the Ferrites for me if I palced an order for a NEW c421 Vlack edition? Like asked for the replacement on the new model as opposed to sending it back later