good numbers indeed... but you're missing one *minor* detail there, that car is no longer runing the stock turbo, but rather an upgraded one with a larger compressor wheel..
I also think that along with the hydra were bigger injectors, but I'm not 100% on that.
FWIW, theyr'e saying the turbo upgrade will only be about $500...
edit: here ya go.. details..
Setup on the car: FM downpipe and exhaust, modified IHI turbo, 550 cc injectors, hydra ecu, big filter temporarily stuffed on turbo inlet, FM intercooler.
(at ~11psi)
http://mazda-speed.com/forum2/index.php?topic=1824.0
standalone $1450
turbo, ~$500
DP 305
Exhaust 599
injectors? ~200 (?)
Custom intake ~200
FMIC $730
So you're already at just over 4k with no install... Good power, but I wouldn't call it cheap!