I chose the vette, for one reason. A viper as a DD will suck, at times anyway. My uncle has a silver 04 that he drives pretty much daily during the summer, but he much prefers the z06 in colder times of the year. I have driven many vipers myself, and they're awesome cars, but very raw to be driving daily imo. The vette is still 400 hp, mod friendly, and just a much better car alll around as a dd.
Very tough decision tho. I know when I would have a very hard time not going with the viper. Good luck
EDIT: I would go GTS ACR tho