Based on ~10 years of experience modifying/tracking and daily-driving turbo cars, my vote would be to stick with the V8. The turbo technology, and the power that comes along with it, is amazing but long term ownership can prove to be a PITA. Services get way more costly at 50,000+ miles on a lot of these cars, and determining something like a boost leak is a huge pain and happens often as miles increase. Factory components are typically inferior for the long haul as well, I remember vividly digging through my favorite car (2002 Audi TT with a big turbo, awd, watermeth inj) and replacing parts that failed prior to modification. Factory diverter valve used a rubber diaphragm, plastic impeller blades on water pump (60% of which were gone/damaged), etc. That was a bear, but Audi's 225hp 1.8T had tons of support behind it...a 3.3T Genesis in its first few years of production? No thanks.