A different Q on 340 Vs 416

I'll take a different approach, and ask how and where will the car realistically be driven for the vast majority of the time? If it's going to see a lot of track time, then you really need to look into the technical side of things and determine what will be best for the ET slip you're chasing. The previous replies offer good advice in that regard.
But, you said it's a "fun" car, which to me implies that it will mostly be driven on the street with maybe only a few dragstrip passes once in a while. If that's the case, I'd go with the stroker. For stoplight to stoplight fun and the pure thrill of sticking your foot in it once in a while, nothing beats cubic inches. Having to rev the motor to the moon to go quick isn't as much fun on the street. Lots of low RPM torque, is!
Admittedly, I'm an "old guy" but I have seen many guys build cars that might be really good drag race cars, and then only take them to the track twice a year, but put on 4000 miles going to cruise nights and car shows. They end up with a car that's not as much fun to drive on the street, even though that's where the car actually spends the majority of it's time.
Be honest with yourself when making these decisions and in the end you'll end up with a car that's a blast to drive, plenty fast, and a joy to own.