As far as being able to log into your online account to see your call details, it doesn't matter the type of phone you purchase. As long as you register for an online account you will be able to see that information. However, pre pay accounts will not have the same functionality as a post pay account online.
I switched from a prepaid plan with AT&T to Verizon Wireless due to coverage area; however the prepaid reporting from Verizon is terrible. I cannot find out who called/texted in nor when it happened. Having a teenage son this is of utmost importance to me as I need to reassure myself that he is not using his phone at the wrong time (while driving) and for the wrong purposes. Verizon Wireless says they don't have room to track and save this information. Oddly enough AT&T can do so and this is a standard part of their prepaid plan. I find this to be a real problem with Verizon Wireless and am seriously considering moving back to AT&T. If you have AT&T coverage, I think they are the way to go if you need any kind of useful reporting.