I would think the 50MB a month plan would suffice. I just checked my last 3 months and not that data usage varied from a low of 3.5MB to a high of almost 7MB. I let the traffic update run pretty much whenever I'm in the car. That said, I do have a fairly typical commute - approx. 1 hour each way, Monday through Friday. If that profile doesn't fit your usage, you could burn a lot more, of course. Fortunately, I was able to go to AT&T's unlimited data plan for a net $5 extra a month. I had had their basic media package on both my and my wife's phone (2MB and 500 text messages) and since my wife doesn't use data, I upgraded to unlimited data on my line, dropped the plan on her line and added a 200 text message bundle to both lines. Geez! I just reread that and could these furshlugginer phone companies make their rate plans any more complicated?