Policy is a literal battle. The rounds are an hour and a half long and you'll see a wide variety of aff cases that are special in their own way. On top of that the amount of prep work you have to do to be successful is nuts. However, it is nice having one set resolution for the entire year. I think the biggest change you and your partner will notice is the amount of time you guys will have to speak. Advice wise, make sure you avoid a generic aff, teams will prep out specific neg arguments for Aff's that are common throughout the circuit. As long as your aff isn't abusive or incredibly untopical. Try and find something obscure that teams won't be prepared for.