I think the earlier model Vipers took a bad rap because of a bit of an over-steer problem. I also saw the article you mentioned and was glad to see that seems to be corrected.
I just sold my 911 earlier this summer after getting the Viper. I must admit though that, at least with my two cars, I could take tight corners faster with the Porsche. Probably a simple matter of physics with the rear engine weight. The difference isn't great but for instance, a tight 180 degree corner near my place I was able to take at about 50 mph with the 911 and at around 45 with the Viper. That is, before swinging the rear end out (not that it couldn't be done faster, but that was the break point without swinging). Now I know that isn't a fair comparison because there are lots of variable...tires, etc. The handling also is completely different so as I get more used to the Viper I will get better (I had the 911 for 4 years and was very familiar with it). But the cars do handle completely differently. The Porsche had to be made to go into the corner and gave you the impression it would rather straighten out while the Viper seems to want to dive into the corner.
I am certainly not a professional racer and I'm sure a lot of people on this board could and will debate this until they are blue, but my experience on a late 80's Porsche versus the 94 RT Viper is all I have to compare. A new GTS or ACR could probably out handle the 911 I had easily. But that's my two cents.
By the way, I did say I sold the Porsche so the handling wasn't an issue!