Lever is more practical. Take into consideration people with arthritis or similar, who can not grasp correctly. A bathroom should look good, but most importantly it should be functional for everyone.

I've wondered about the practicality of that style too.

Our first house had 70's plastic taps with gentle curves that were troublesome enough, progressed to the four pronged style which was easy to turn.... and turn and turn, now have levers, and the only improvement on those I can imagine is motion or voice activated. Perhaps those circle taps have a non-slip surface treatment which helps with grip? Though if that's the case does the surface also hold dirt and soap scum. It looks like an illogical design for the purpose but I'm interested to hear from people with personal experience with them too.

I would avoid them at basins or showers and make sure you use the lever tap. They would probably be fine for a bath use as hands are generally dry there but why bother if you had already used the lever tap elsewhere.
Two taps are annoying anyway when you're trying to get the right temperature. Mixer taps were invented for a good reason.

@macyjean - no non-slip surface treatment.

Yes I wanted mixer taps for pretty much everything. The Circa have been proposed for the bath tub so yes but also possibly a guest powder room (have to double check)... might be ok but would love to hear from someone who might have gone with this style and share their experience. I’ve played with it on the display but no water or soap to really road test it 🤗😬