We have a tub from Richter and Frenzel.
BUT: I agree with the others, the shaft behind it would be way too complicated for me. There has to be a lid on it so that nothing accidentally falls in – in the end, I would always climb into the tub to lift the lid with one hand and throw something in with the other, because standing in front of the tub I wouldn’t be able to keep my balance while opening the lid.
Aside from that, I would URGENTLY advise you to try lying down in the tub. Really slump in as if you were in it with water, not sitting. Otherwise, you could just save yourself having an uncomfortable tub that is never used.