So you have two choices.

A male that is very loyal and committed only to you. Guy A

A guy that is loyal and committed, but not as much. Also he wants an open relationship, he wants mistresses on the side. Guy B

Guy A and guy B. Guy B has higher smv.

Which one do you prefer? How much higher does guy B need to be on the 1-10 scale? 1 point, 4 points? Most women would pick guy A If he were a 6 and guy B a 7. Buy what if guy B is a 10 vs guy A as a 6?

Does it matter how the smv varies? For example if guy B is a 10 in looks but a 6 in resources/power/status does that make an open relationship less desirable than one with a guy B who is a 6 in looks but a 10 in resources/power/status? Or the opposite?

At what point does a higher smv in a man become a good trade off for less fidelity? And does it matter why his smv is higher (looks vs resources).