late breaking news.. JMS is not owned or operated by Chris Johnson. superchips merged w/ JMS an Chris is now the head engineer over product design for them. sucks because i think quality was more carefully monitored when chris was tuneing his JMS chips, but maybe that means the quality will go up w/ superchips now.. any way he's moved to florida to where superchips is located.
you can buy preburnt jms chips, but to do it the right way ya needed to have JMS dyno tune your setup..all the cars on his list of customers in cluding a local b'ham guy (brian bradford blown stock 984v)-dyno tuned the car an custom burned a chip for it.
diablo has different methods. you can buy a pre burnt chip or you an find a tuner to do it. guy locally does it w/ blank diablo chips an delta software from diablo. but you need a dyno to do it as well.
local dyno guy told me that chris is in the works of a handheld tuner similar to a predator setup. similar to a tweecer, but supposed to be easier to tune w/.