What do you mean by service? If you want a girl that do a laundry list of erotic steps like licking your feet, balls, rimming etc then Japan or Macau Saunas would be it although communication would probably be an issue (assuming you don't speak their language). If you want a sweet GFE type girl that will stay with you longtime in your hotel then Philippines or Thailand you can find many that treat you like a BF.
A mix of the two. When I say "service" I really mean a combination of service and attitude: basically, a high libido / strong desire to get off from what you're doing together; leading to her wanting to do freaky shit
because it's what gets her off, rather than upcharging for it.
To me, sex with an SP who's very "service-oriented" should be similar to gay sex with a bottom dude, or to sex with a girl who's "partying" on certain illegal drugs — in that the person you're in bed with is (or seems to be) there
to get off just as much as you are, and is treating you as an object to satisfy
their lusts. But, y'know, by being a "thirsty" bottom / being aggressively submissive, rather than by topping you/being aggressively dominant.
Obviously, with SPs this would be mostly an act (unless they're very low-volume and you happen to be exactly their type.) But to me, the ideal service-oriented "performance" from an SP, is one that makes me
believe that I'm someone they picked out to hook up with. Not someone they emotionally give a damn about (GFE), and not someone who's professionally trained in all sorts of sex techniques (PSE), but rather someone who's just a horny, freaky pervert of a woman; one who will try to get me to keep fucking when I stop, because
she needs it.
I think the better question to ask for someone who has never been to Asia is, what type of Asian girl do you prefer (East Asian, South east, tan or white skin etc) , what is your budget (cheap like in Philippines or $$ like in Japan) and do you need the girls to speak English (Thailand, Philippines, Cambodia)
Those are all good questions for most people. (My answers aren't that helpful, though: I love all the body types, and prefer
novelty in women more than anything; my budget is arbitrarily high; and I already know several Asian languages and enjoy learning them. So I can really go anywhere.)
The key distinction I want to know about is something like — in which of these countries are the people the least prudish? In which country is a random girl off the street most likely to be into weird kinky shit even when stone-sober? In which of these countries do the locals have the most casual sex? In which of these countries do the girls have the least attitude of thinking of their body as being a highly-valuable object for men to fight over, and the most attitude of thinking of their body as a medium for attaining pleasure?
(For a concrete example from another continent: in Africa, by these metrics,
Botswana is the clear winner. There's a thriving market for male prostitution there, because the women are so horny
and non-prudish that many of them are perfectly willing to pay for sex! And this means that there are few female prostitutes in Botswana — there don't need to be, because it's so easy as a man to find a desperately-horny woman who's willing to settle for
any sex, the way men do in most of the world. And, as a bonus, the women are xenophiles — they prefer foreigners to local men, not because of wealth, but just because foreign men "have a better attitude toward pleasing women" than local men do. [I've never been to Botswana personally, but I've hooked up with several women from there over the years, who've all told me the same thing.])