Does anyone have experience with a narrow bathtub 170x70?

Good evening everyone,
our bathroom will not be very large and my girlfriend wants or needs to have a bathtub. Now we are considering choosing a narrow 170x70 cm version. My girlfriend is about 163 cm tall and of normal build. Is such a narrow version still to be considered a normal bathtub in terms of comfort or does one feel very cramped? Unfortunately, we have not been able to see any in person yet, so I’m asking here.
I will hardly ever use it myself, showering is enough for me. We also have two children, 6 and 8 years old, who might still shower together for a while, just as an additional note.

For example:
Kaldewei Classic Duo Rechteck-Badewanne weiß mit Perl-Effekt
or
Kaldewei Cayono & Cayono Star Rechteck-Badewanne weiß mit Perl-Effekt

We had a 180cm long bathtub. It was almost too long for me when bathing alone, I am 164cm tall. Unfortunately, I can’t say anything about the width, I don’t remember anymore. But the dimensions should be sufficient for one person.

I had it in the bathroom of the townhouse. I am 165 and weighed/weigh 58 kg. I was never covered by water. I hated bathing. We then replaced it with an asymmetrical oval one, really stylish, it had legs measuring 160 x 100 and was 5 cm higher. We could then bathe in it together.

170 x 70 is not narrow but nearly standard (170 x 75). It would be too small for me, but for a person of 163 cm it will be completely sufficient. However, it should be said in general that not all bathtubs with certain external dimensions offer the same bathing experience, so I would actually try lying in them first.

Thank you for your opinions. We actually found two 170x70 at the hardware store and tried lying down in them! And as K1300S already suggests, 70cm outer width does not always mean identical inner width. In any case, the 70cm wide tub is enough for my girlfriend, it is a compromise if we want a tub in our "small" bathroom.

If necessary, there are also smaller girlfriends; I've also seen that once at the hardware store-