AJKS: From what I am aware of this is a lot like the Stillway 0-400 Supra sequential style shifter except that it disable manual lockout and you'll have only the up/down shift pattern. The look of the entire unit also looks like a real sequential unit, unlike the Stillway which retains the look of the factory 6 speed.
Here is a link from one of its distributors:
http://www.takakaira.com/performance/ikeyaformula/ikeya_manual.html about the Ikeya unit, explaing how it works, and its basic design.
Moreover, I've C&P'ed some info from another forum regarding the IKEYA:
"The unit is basically a non-electric, non-hydraulic, mechanically geared device which simply converts the shift knob's fore and aft movements into the regular |-|-| pattern underneath, where it is connected to the transmission. The clutch is still used for all shifting. I doubt it can shift much faster than a regular transmission equipped with a short-throw shifter, but at least it eliminates missed shifts. It would probably be most effective in road racing, but will likely be a pain in the rear for street cars, being that it doesn't seem capable of entering neutral from high gears without pushing the stick several times (it has a R-N-1-2-3-4-5 pattern). Also, engaging reverse requires disengaging a safety which looks a bit cumbersome. Something else to note is that the contraption extends upwards from the transmission tunnel, so looks a little hideous--also a sign that it's really made for the track. Interestingly, my biggest complaint is also its best selling point--the price. Close to a $1000 pricetag, it's a real bargain when compared to entire sequential transmissions. But at the same time, the small unit comprised of simple moving parts and a small gear meter doesn't seem worth all that money. I guess what you really are paying for is R&D. They've made it for some Skylines as well, and a few more applications are on the way." HTH