I have a standard '04 plate MK4 Astra GSi Turbo as my daily driver and I couldn't recommend one enough. It's a very quick car in standard trim, can be had within your budget and it costs me £600 a year to insure (26, no claims, convictions or mods)

I have so much fun showing up people in it.

I've had it 3 years now and it's only ever cost me tyres and a backbox. Pretty good if I dont mind saying so. I can only speculate that the issues people have with the Z20LET are sue to poor servicing or cheap oil. I use Fuchs Silkolene Pro-s 5w30, a genuine GM filter and sump plug every 12k miles (once a year) and it's still as smooth and quick as when I got it.

Lee