Against:Got to say, that before I bought my spider 2L, I test drove a V6. The problem with it was, the ground clearance was poor so every speed hump meant slowing down to the signed speed. Go into the driveway resulted in scrapping noises. And it does not matter how you say it the physics of having a heavy engine up front means weight balance is worse than 2L. Also big difference in the ride, the 2L was less crashy. I could also watch the fuel gauge go south when driving, the 2L didn't move. So if you live in the real world and you need it for everyday use the 2L is a better option.
Mate of mine had a V6 in Alfa 75, great balance in corners, with the gearbox and the diff at the back where they should be, but not a very pretty car though.
The V6 acceleration was impressive on the GTV , O'yes the sound, the beauty of that V6 is fantastic, if one came my way again I would buy it. Heart over the head, wins hands down.