I wonder how I can differentiate them?
I went there yesterday as well. Overall the quality of the guys went down in my opinion but it could be just this week. I never struggled to find a good guy before but yesterday I ended up only one guy, who was actually visiting from Sao Paolo. I think he was fairly busy but performed well and had a good attitude. So I wwas happy but couldn't find any other potentials so I left around 7:30.
I also ran into another romanian, who was just aggressive. As soon as he said hi, he wanted to go room. I usually ask what they like, whether they kiss etc, guys usually spend at least a few minutes (not even 5!) discussing what we can or cannot do. Bbut this guy just asks me to go to private room in every second I say something and was super pushy without telling me what he likes and can do. So I asked him where he was from. ROMANIAN!!!!!!! Instant no!