Ask HN: Which pricing model do you prefer?

I'm trying to decide on the best pricing model for my service: www.initialround.com

I've narrowed it down to the following two: 1. Fixed price plans per month based on number of interviews sent out (this is the current scheme) 2. Fixed price per interview sent out with a free quota per month.

The second has the obvious advantage that you pay nothing if you're not currently hiring.

Also, for the second scheme, what do you think is a reasonable price to pay? I was hovering around the $3/interview mark with possible discounts for bulk purchases.