Well it was time to upgrade the tires on my car. The wheels that I have are from ASTRA SRi. 18x7.5, and OFFSET is 37mm.
OEM Tires were Dunlop Sport SP01 225/40-18 (OLD TIRES)
NEW Tires are Continental ContiExtremeContact. 245/40-18 (NEW TIRES)

Total cost was just under 700$ USD
First impressions are that they are much more quiet then the Dunlops and also more grippy.
And Pictures from the Installation...

And yes even tire rack can scratch wheels, they scratched mine, and denied it. Luckily it was small enough scratch that can be fixed by buffing.
And here are the comparison pictures between the two tires. Old ones on the left, New ones are on the right.


And here is how they look on the car...









Page Content.
1. Introduction
2. '04 GTO Brake Swap.
3. HID 5000K Install FOG/Lo Beam.
4. Steinmetz Cat Back Exhaust.
5. H&R Rear Wheel Spacers. +2"RW (Saab)
6. 18x8 Astra Wheels.
7. Front Lip.
8. New Continental Tires.
9. Red Striped Grille
10. VW MEET
11. Chrome Stripes
12. Mud Flaps
13. Headlight Eye Lids
14. Corvette vs GTO Pads
15. Exhaust.
16. Front/Rear Wings
17. Moda R1 Wheels
18. New Control Arms and Sway Bar Bushings
19. GTO Springs
20. FX-R BiXenon Headlight Upgrade
21. Licence Plate LEDs
22. Homemade InCar Camera Mount