test-fuck
To "test-fuck" is to have sex with somebody for evaluatory purposes. You can test-fuck somebody to determine if you'd like to fuck them in the future. You can also test-fuck someone for a friend.
"I think you're pretty foxy, let's test-fuck to see if we're sexually compatible"

"I am coming to New York next month, why don't you test-fuck a few hotties for me, and find me someone suitable?"

"I thought Leroy was pretty cute, but after our mediocre test-fuck I decided he wasn't worth a second date"