instead of watching the road, or your tach on a dyno, you are going to be watching your - tach, boost gauge, a/f meter, a multimeter monitoring VF and know exactly how far you have the accelerator pressed
in addition, when were talking about it's sampling rate of 40-60 times a second, you're telling me you can see that and have no need to datalog
look, some people like mandarins, some people like oranges. both are yummy tasting citrus fruits. so it doesn't matter which one you get if it has the features you like but you cannot intelligently say that datalogging is just "look what i can do"