Nothing is as failure prone as a turbo Scooby.
They will always be slow, it's the inherent worthlessness of the design
As far as expensive, I just watched a kid fork out $2000 yesterday for a bunch of fancy bolt on intake/charge pipe/exhaust parts that in no way shape or form makes his STi faster. Oh, it's an 07, so it'll shit a piston... probably before the parts arrive and are installed.
AWD is hype, a dinky ass chihuahua head sized turbo is not worth acknowledging the existence of, you're right there with Johnny claiming 30+ mpg out of a platform known to get less, and the complete LACK OF PERFORMANCE and LACK OF BUILD QUALITY do not make it practical.
BTW, Corvairs don't blow up, Nader is just a faggot.