I think the following conceptual diagram will help some folks on the general power vs. torque and closely related overboost topic.
Here we are comparing the following engines; normally aspirated engine (green) vs. a turbo charged (or turbo charged with overboost but
without peak power gains) (red) vs. one with the same redline but higher peak power (rather than same power and more torque like red) (purple) and finally a higher power and higher redline engine (blue). Yes, certainly not all engines are at all capable of such a nice linear response as the green baseline curve so it already represents a fairly high performance engine (very E9X S65-ish). Nonetheless, even with other qualitative shapes of power curves such as the somewhat typical humped shaped curve (think most Corvettes) the principles here still apply. Of course the shape of the turbo curve here is also not qualitatively like all turbo engines, it is more typical of modern BMW M turbo engines. Again, concepts still generally apply.
The point is that red certainly is better (i.e. offers more performance) than blue. However, in choosing between possible options and comparing to the baseline (green) to a more torque same (peak) power option (red) or more peak power (purple) generally the higher peak power option (purple) will deliver more broad spectrum performance improvements. Yes, you will have to drive it at high rpm and if its rpms drop often and well below the plateau level of power from the turbo engine, it will make for a much closer contest. If it is indeed kept in the high rpm range, it will on average consistently produce more power and that is better for performance than making more torque. Of course the highest performer of this bunch will be the blue engine that makes the most peak power at the highest rpm.
If BMW is indeed making the new M4 "S55" at the same power level as the current car this would be a bit like current M3 = green and new M4 = red. Yes red is better, better because of the increased POWER available at lower rpms. However, in almost all contests, something like the purple car would produce better performance. This is the classic "torque vs. power debate". The blue curve is then something like a Ferrari 458, not much of a fair comparison with both more power and a higher redline.
These curves tie right back to my previous comments also about an engines feel. Unfortunately, one can REALLY feel the flat table top part of the red curve, it just feels like the engine hits a bit of a performance wall (technically a "breathing wall"). The acceleration tapers off and then stays constant rather than increasing all the way to redline like the other cars/curves. This provides a much less exciting and race car/superbike like experience. Most of the normal aspiration M "purists" are obviously greatly disappointed about this particular qualitative and quantitative change to the engines character and thus the cars feel. This does not even touch the concept of turbo lag....
Of course if one is to simply reject the proper use of gears and rpms, again a "lazy" driving style, the turbo car will be more more suitable for them as it makes more midrange power. I guess this is just the fairly common but loose claim that torque is basically midrange power. Certainly a boost in torque in the midrange, along with an inability to produce more torque at high rpms does exactly this - boost midrange power without improving peak power.