100 to 300 is triple the speed. In an instance where you need to burn say 10km, it would take you 100 seconds. With said example, that goes down to 33 seconds. That’s not trivial by any stretch. It’s a minute where you are not in space at risk of being attacked in an insanely slow ship, or a minute where you’re shooting things rather than burning to a gate. Ideally you’d be burning as you shoot in which case the extra speed would possibly harm your DPS application.
In short, the AB is built for sustained speed improvements, and as a result is not only easier to fit but much more sustainable.
In the case of being useful for mechanics stuff like transversal, use an MWD. That’s what it’s for. You pulse it when you align to a good vector (which is likely exactly what you are already doing).
If you want both, fit dual props. I’d argue that’s just as expensive of a fitting decision as taking 33% of your rig slots + whatever calibration cost and drawback cost.