I'm eying a really nice set of wheels now, and I'll stick with the 19's simply because I have the six-month-old tires that are warranted for 50K. The wheels I will be getting are just a shade lighter than OEM, but not by much... maybe 5 pounds. They're still porkers, at 28# each.
I don't track my car though so it won't be a huge handicap. Most of my "aggressive" driving is done on twisty roads like the Dragon, mixed with some 145mph runs on Mexican interstates at 3 in the morning
**EDIT** I've heard the OEM Limited 19" wheels weigh 36 pounds, while some have stated 33 pounds. I've never gotten a straight answer of the weight of JUST the wheel. I know the SRT 19" is lighter, since it's forged aluminum, not cast wheel.