I am considering spoiling myself with an XMP3 for Christmas. Question: Am I able to just have them bell me monthly, and set up an online account and pay my bill at my leisure? I never let anyone automatically draw any bills from my account. I prefer to do it myself. And... If I can set up monthly billing, will I still be able to get the $30 mail-in rebate? Or will I have to pay for 6 months service up-front? Thanks.