Identical looking saddles feel very different
I think it is the difference in stretch, a slight different of angle in 'give' will make a huge difference in how they fit you.

It is often but not always that the more expensive saddle is the better one.
I have had a very cheap (4 $US or less) that I used without problems for all its (rather long) life.

People who use saddles with a gap will often tell that those work very well for them, but not for all people.

So I am afraid it will be a case of try and change if it does not work out.
If, as you have, you find one that fits you, try to get one for each (new) bike.