I am considering using these to help me last longer in bed.

I will be fucking a girl. I'm under pressure as she been telling eveyone I will be staying at hers tonight.

I have also heard that she is also very nervous (I assume she wants to impress)

I will admit it. I find her very hot. Kissing her in public I've got a full on erection.

Has anyone ever used these? Do they work?

Do they dull erections and increase refractory period?