This is my first post here it's great that I get to explain the pro's and con's of MP vs. SP
Cost can sometimes play a factor. Most SP's I've been to charge around $100 (incl. greek), $60-$70 straight. I usually go the greek route when I go out. It costs less than MP's. It does usually feel very rushed, I try to work in as much heavy petting and body kissing as possible before it's over, or even begins, and remind them I have half an hour. The room usually feels like diseases can be lurking everywhere too.
It also depends on how much time I have. If I am short on time I will choose an SP, but if I have more time (and more $$) I will visit an MP.
The number one thing I have found (which other users have gone over) is that the MP is overall more fulfilling. I get more time with her, she spends more time on me and it is very relaxing. I usually pay for 40min, and no more, but I always get 1hr with the girls. I like to take my time and give them a real massage and kiss their body. While I leave SP's feeling very dirty and wondering how much satisfaction I really got.
Another huge factor as to why I often find MP's more appealing is the risk factor. I am hitched and would find it very hard explaining to my wife how I ended up getting booked with an SP. Legit venues are wonderful!!
In the end, MP's are more favourable. But sometimes I just want to full-on service with an SP (like today, maybe). I hope that helps.