In my opinion, men should avoid dating services that are set up for Ukrainian women to meet foreigners. Sure, there are good ones out there, but the sheer number of scammers would simply wear you out!
I just arrived in Kyiv and don't know how good or bad it is here. When I was in Odessa, I've heard some scammers sign up with these dating services. Since they are real women, no dating services would turn them down. However, these women are not interested in dating you but only pretending! They would open up very quickly and charm you. When you decide to take her out to dinner, naturally, they INSIST it must be a particular restaurant of her choice. It turns out they are getting a commission from the restaurant for taking you there! I've heard online that guys ended up being charged $600 or thousands at some sushi bars. Before you even ask, calling the police wouldn't help because these restaurants have already paid them off!