I wouldn't try all those positions with SGs unless your ScatManDoo who negotiates first with them, and knows the girls who would be willing to do all these kind of positions. The worst thing that could happen to you is getting a SG for $20 bucks or 200 pesos, and you want to do other positions and she tells you, OK $10 each position. If you wait she'll usually come around $5 dollars each position but it's better to make a deal before you go up. BTW the standard position for SGs is missionary.
The best thing if you want to do different positions is get a Bar girl, because theoretically you can do all the positions you want with them, but I could see they might object to the more unusual positions if you pick the wrong girl.
Yes Amigomio I heard that too, and some girls even make it do it doggie to them, but I like doggie, and always say OK. But at the same time many providers dont' like mongers back there doing doggie, because they can't be sure they aren't trying to take off their condom, or putting their dicks in their ass, so many providers also refuse doggie for these and different reasons.