This month, JBL released three different On Stage models in the United States: the $130 On Stage III, its iPhone-compatible follow-up On Stage IIIP ($170), and a brand-new $150 product called On Stage 200ID. Confused? We?ll sort all the details out in a moment, but the simplest explanation is that if you?re looking for a high-quality portable iPhone speaker system and willing to pay a higher than typical price, start by checking out the?