As Davie says.
But also your overall gut feeling once the deed is done.
I had a punt at the weekend which I'm still mulling over. At the moment I would rate it as a neutral but there's definately aspects that could, and quite possibly should, make it a negative which might yet happen. The saving grace was that I found her bloody good fun, full on and it was quite exciting overall in a way that I haven't really experienced since my street walker punting days.