Hi I'm currently running a Hirsch 2.0l LPT which only had an ECU and APC valve upgrade. Running at 215 BHP, 65 horses higher then the standard 150 bhp. It was the best £1000 I've spent on my Saab.
Although it did lead to spending another £1000 on some Super Aero 16" wheels and fatter tyres to give it better traction under cornering and acceleration. It also gave the car a better ability to handle the extra power, it also made the ride slightly firmer but without loosing the 9000's comfort and relaxed cruising style.