In that situation, I'd probably take $1500+One Spin. I'd worry that I'd run through all the spins, whammy on the last one and lose. If I had even one spin in the earned column, I could pass it in hopes that my opponent would whammy.
In watching GSN reruns, I'd forgotten how many times a whammy was hit on the very last spin of the game. It was mentioned in an earlier post about that guy who hit a whammy and lost $30,000 on the last spin - I'm pretty sure I don't have that one on tape, but I'd love to get it.
As for passing, I always think of \"the $2000 rule\". In the second round, it's pretty easy to get $2000 on a single spin. So I was in the lead by $6000, I wouldn't pass unless I had 3 or fewer spins left. 4 would be too easy to pass my total.