There's no need to debate or tune anything. The M50 manifold has larger runners and makes more power, period. It's been shown an endless number of times on dynos, even for those who can't clearly see the difference in flow (it's hardly subtle). More importantly, it doesn't fall off at the top end like the M52 manifold. And the difference isn't outside of the range of the system to require any tuning. More flow simply means you need enough fuel to match the extra air. If the DME couldn't keep up, you'd see injector duty cycle codes. Don't waste your money on tuning and enjoy the extra power.