I'm confused on if i should keep my ts or trade/sell it for the more powerful 3l v6 75? a sunroof is in my head and thats another reason why i would sell it for 3l with a sunroof. i guess you almost could make the twinspark as fast the 3l by adding performance features. but having the 3l and adding the performance features to it, would just make it a weapon. i would still would use as a street car.. any advise on what to do, keep or sell? 

-thanks, daniel 

I think you have to go with what you feel like, as you say both can be quick. If the car you have is good and sorted I'd be tempted to keep it as you always throw away a bit of money when buying/selling. It already has the right gearbox, with a 24V engine as Brent suggests it will be a better weapon than a stock 3.0L.