In general I would say:
A good service from a WG will depend on how much experience she has and if she likes fucking in general.
Some are able to achieve multiple real orgasmen (even with not so handsome men),
and others want to get the job done quickly as possible.
Experience comes with the age, so naturally the older WGs are more fun in the sack then the really young ones.
If she is a 8,9 or 10 in looks is relative and is in the eye of the beholder, but I would say the younger ones looking
naturally “fresher” and ”better”. I guess the stunners are more in the younger group than in the older group to find.
And here lies the contradiction.
I not would say the stunners are not so good in the sack, in comparison:
the younger girls are often not the killer fucks.
Result: I prefer the older 10s who like to fuck.
(but agree they are not to easy to find)
Just my 2 baht here.