And you agree to what? Honestly, my biggest problem with SA is that if I am paying then I am more interested in the bedroom than the chatroom

if I want a real relationship shouldering someone else's problems then I go to OKCupid.
Also, a few hundred per what? Meeting? Week? Month?
I would assume he means per meeting.
If you want a monthly arrangement, the average tends to be $3,000.00 per month for roughly 8-10 meetings per month. Some women are ok with $2,000.00 per month. Hosting is of course an issue - if she can host it is less expensive because you do not have to get hotel rooms every time.
On a per meet basis the average request is $500.00 each time, though I have found that most women are ok with $300.00. Again, lack of hosting can up this if you need to get a hotel room.
The per meet ones are closer to an SP, though the meetings are not as fixed in terms of time. Most meetings last at least a few hours - on average 3. There are also no fixed parameters about what can and cannot be done - ie it is all open for discussion. Certainly the "multiple shots on goal" is never an issue. You shoot as many times as you can.
It is an interesting comparison between SPs and SBs. SPs are more "efficient" and less "work", if I can put it that way. So in that sense I agree with Dickson that if you are just looking to meet for a certain service they are the preferred route, as there is no concern about getting involved in their personal lives, and very little concern about the meetings being exposed, particularly as SPs very rarely will know your real name. SBs run more of a risk of getting dragged into personal matters, and more of a risk of being exposed if the SB gets emotionally attached, particularly as it is very difficult to see them frequently without them knowing your real identity. That said, the meetings are longer and more "gf like", and if you like to see your partner enjoying herself and having orgasms, SBs are in my view better for that, as they are not professionals in this type of business (some are but you can usually figure out who is and who is not), and given that you will tend to be their main source of sexual contact, they are more inclined to want to orgasm (usually multiple times) during the meetings.
Both SPs and SBs have their good points and bad points. Kind of depends what you are looking for. If you want simple sex, SPs are better in my opinion. If you want a more intimate gf experience, than SBs are preferable in my opinion. Problem with SBs, as pointed out by Dickson, is the GFE can go beyond the sex part and become more of a real GF, which could get uncomfortable if that is not what you are looking for.
To each their own! As long as everyone is happy and satisfied with whatever relationship you are doing, be it SP or SB, or a combination of both, all is good.
WH