There's good and bad with having a pump that turns on each time you need hot water. The small tank and pump with a pressure switch resembles a well pump system. It's advantage is it's simple, but the tank will eventually need replacement plus, the pump won't turn on each time you want to wash your hands.
The inline pump's flow switch may get cranky and not turn on at low flow (which might be a good thing sometimes), but they are less robust than a pressure switch. ANd, assuming you do not exceed the minimum flow requirements, you might find a very fine line between when the pump is off and when it turns on which could lead to some weird results as the pressure suddenly spikes when the pump turns on. Hopefully, it has a soft start which should limit the effect.
Not having ever lived with either, I can't recommend one over the other and my thoughts are theoretical, based on how they generically work, not specific experience. But, if I were to do this myself, and the slightly larger footprint wasn't an issue, I think I'd go with the tank and pump verses the pump only.