I voted V6...
With the exception of the engine failure shortly after buying the car (no oil in it for thousands of miles, dealer/previous owner's fault, not mine) I have had virtually no problems.
When the new (Ford rebuilt, put in by a dealer) motor went in, the OEM coils were reused - against my suggestion, and willingness to pay, for new ones.
So I have had to do only a PCV elbow and coils on my V6.
I had zero engine related problems with the car. And I ABUSE it. The engine sees the rev limiter several times a day, included many hard launches.
I change the oil every 5,000 miles and have put roughly 55,000 miles on the new engine with, again, zero problems.
I know the V6 (especially my 2000) is down on power compared to the V8, but it has enough pickup to get you in trouble.
My mileage is horrendous due to my driving style, but then again, I bought a RWD Lincoln that runs on premium gas... If I was worried about gas mileage, I wouldnt have bought the car.
To each their own.
Plus, Xpipe and magnaflows sounds sexy on the V6