If 5th gear is never grabbed, then I believe there will be no difference since I don't think anyone will log a diff btwn the '09 and the '10 winglets and its a mod to make the car feel more stable at high speeds (I don't let out due to instability, so I doubt someone with the exp of Colonel would do so) not nec go faster.
So as I see it, the issue is how much would you use 5th gear at the Ring, if at all? I don't know, but it seems to me that if Colonel never grabbed 5th making his record setting run in an '09, it is questionable whether he would grab 5th in a '10. I think he could tell you, so maybe before anyone spends $40-50k of VCA money, someone should get in touch with him.
Keep in mind that some drivers like the feel of less revs. Cindy Lux (based on things she has posted about high revving engines) would prob use 5th gear as much as anyone, and she is a Dodge test driver who I think has tested the '10 as much as any Pro...so maybe someone should get her input. I would be curious if she uses 5th at MMP, where on the Outer Loop I would redline in 4th on the main straight. That would prob be a good track (Outer Loop) to test the two cars. I have never run with a '10 there, but would be happy to show up with my '09, however, my car has some mods and upgrades so we would have to find a '10 with similar mods to make a valid comparison. Keep in mind that these cars vary on the dyno about 20 mph right off the truck, so the best comparison would be two stock cars that dyno the same and then use the same driver on the same day on a track where 5th gear is usable.
As for the 7 secs diff btwn an '09 and '10 going from 160 to 180, I think that's a high estimate, but I really don't know. Again, maybe ask Cindy.
Personally, I think I would rather spend my money on a VCA raffle ticket and see the surplus go toward more VCA/Dodge presence at USA race events.