just looked over this thread. I don't know anything about the Ecotec's, but know a little too much about the subarus.
one thing to keep in mind. SVXs are big, heavy cars with very torquey motors. transmission failure is VERY common. Also, they're very unique and rare, so other parts are valuable.
I know of a few guys who were able to buy a complete car with a failed or failing trans for less than a grand. keep the engine, wiring, ECU, etc., Sell the fenders, doors, interior, glass (lots of curved stuff, very hard to find!), and make a couple grand or more! depending on how actively you try to sell them.
I did the wiring for a guy who put an EG33 in his 2001 2.5RS. he paid me to drive across the state, put me and my girlfriend up in a hotel for 2 nights, paid me for about 20 hours of labor (lots of custom stuff....not a straightforward swap. but it'll be worth it), and still came out about a grand up. That's right, engine swap, paying for quite a bit of labor, custom radiator, and a few other not-cheap items.....with cash left over!
Also, 2.2 non-turbo motors are cheap, and bullet-proof. and the logic modules that control the fueling in the ECU are incredibly smart. able to correct for a 5-7psi of forced induction quite reliably. I know of a guy pushing 12psi daily through his 2.2 with injectors, and a higher fuel-pressure regulator.
And there are a few of us putting superchargers on them. I'm using an Eaton M62 off a 2000 Mercedes C230 Kompressor. it's design allows pretty simple mounting without having to integrate it into the intake manifold. and it also has an electromagnetic clutch in the pulley, just like an A/C compressor, that entirely eliminates parasitic loss off-boost. I'll be running it with a Link fully tunable ECU. stock pulleys should yield about 4psi, and almost 150 awhp (consider almost 20% drivetrain loss too). with a larger crank pulley, the rest of my setup shouldn't have trouble hitting 200 reliably at about 8 psi. and this is all at 9.5:1 compression (stock N/A '93 2.2l that I bought for $100, then rebuilt for about 300).
for more info on my build:
http://www.ultimatesubaru.org/forum/sho ... hp?t=92862