Alright, so, i have had this car for around a year and you know what?.... i wouldn't trade it for the world! it has had it's share of problems, not gonna lie. Infact, i have to spring for a new transmission at 200,000(km) because mine is destroyed. 2 windows don't work, the dash will sometimes go dark during night driving and i can see my speed or anything, it needs new front shocks and a muffler. But, this car stills rids good despite all this, it has never let me down and never left me stranded. I still get great gas mileage(car says 28 MPG in 25/75 city/hwy driving!) and great power output. and once i put a new transmission in, i know it will be great, just the way General Motors made it
Mine is a Regal LS with the performance package and EVERY option the car had that year (1999) Heated seats, leather, sunroof, Driver information center below the tach, Gran Touring Suspension, Monsoon stereo system, 16" alloy rims. It is basically a GS without a supercharger (which is fine, 'cause i really don't need to pay for premium gas or get slightly worse gas mileage)
so i suppose in answer to the question, my favorite feature is all of them! :)
I can't lie and say it is perfect, if i were to ask for any changes it would be that they could have given the interior a better build quality. I mean i love the look, quite honestly i think it is one of the best looking cars for an interior i have seen in any car form any year, i absolutely love the look, but a lot of stuff creeks or shakes or rattles or what have you, and that can be annoying on a dirt or rough road. However, you can have that problem corrected for some money, but, it should have been better in the first place. Also, the transmissions are known for having issues, not all of them do, but enough that you should be aware of that before buying.