TD05 20G 7cm. Best all around turbo for the 2.0 imo. Not too expensive, reliable, some lag but not too much, 330whp average with a good tune, and not too hard on the drivetrain (although nothing is guaranteed... stuff happens.).
Mine is a P&P'd TD06 20G, and I'm still on the stock engine and trans 2 years running, with a very aggressive tune. I drag race 2-3 times a month and do some road course as well.
If you wanna go rotated, get the GT3071 or 6.
04 SRR WRX 370whp / 401wtq / EJ205
05 PBM GTO 440whp / 470wtq