My POV now... a pussy is a pussy.. its a matter of how often you want the pussy to be raided by another dude... chances are... lower price pussy = low entry point = a lot of guys can pay up and fuck... higher end pussy = higher entry point = less guys went to raid...
as to whether its worth it or not... its a matter of what you want... and what value you put on a pussy being clean... money you spend have no correlation to the quality of pussy you get... or how pretty she is...
High end ladies aren't listed in an agency. High end should be rare not available to average joe
High end requires:
1) model level looks
2) exclusive access.. not available to anyone who can just call to book
3) high price
Now once awhile u have girls who work in agency who satisfies 1) but that's it. By definition they aren't high end. Nowadays high end are the ones u see on social media who are often travelling.
Now if u are talking about higher end agency, then dream4u is one that has consistently has higher price point and based on reviews i think their quality is fair for their price.
Not sure if there are any higher end K or J agency.. at least i am not aware of it.