I've been on both of these sights for about 4 months now. I've had hits and misses with both. On SA I'm more likely to get laid than WYP, but I've been surprised by the results from WYP since they caution you that "Sex should never be expected on the first date. Please be respectful to all members."  
On SA, my profile states that I'm looking for a sugar daddy arrangement or NSA. I only reach out to or respond to girls who's expectations are "negotiable up to minimal" I'm 48 years old and have about 5 current pics on my profile. I've dated about 8 different girls ages 21 up to 35 and all colors of the spectrum. I never agree to a monthly allowance but offer 100 for a meet and greet and depending on the girl I'll offer anywhere from 200 to 300 ongoing with the stipulation that I expect to sleep with her. They all say they appreciate this straight forward approach. Others have countered with higher $$ but I never agree to anything higher until we've met for dinner or drinks. I did get a good vibe from one 24 year old knockout at the initial meet and since we were at her hotel bar, I agreed to 400. I ended up disappointed since she wouldn't kiss, only cbj and did not seem into the DATY. Every other girl I've made it that far with was gfe all the way except for CFS of course. I don't need to be knocking any of these girls up. I do have a 23 yo beautiful black chick I've seen regularly 5 times now and I'll book a hotel room and we'll spend the night and fuck once in the evening and once before checkout. Not bad for a 250 stipend.  

WYP is pretty much the same except I usually offer 50-150 for the first date depending on the girl. I'm always honest about my intentions and while the initial price doesn't guarantee sex, I'll let them know that if we hit it off I'm ready to proceed to the next step same day if we're so inclined.  

I'm not a high roller, but I am a sex addict who regularly spends up to 1250-2000 a month on the Valley's finest pros and some of their not so finest. I still do but I've set aside a portion of my budget for SA & WYP girls. There's something to be said for actually going on a date, getting to know about the girls, charming them and the satisfaction when the night (or the next afternoon) is over and everybody got what they wanted. My most expensive encounter all inclusive (dinner, hotel, $$, drinks, etc) has been about 500 and that was an overnight in a nice resort with a 9/9 by TER's scale and lasted about 17 hours