In a detailed comparison, Consumer Reports has taken a closer look at AT&T Next and T-Mobile Jump, and the results are interesting. According to the publication, purchasing a 16-GB iPhone 5 would set users back some $1,830 with AT&T Next, while the total cost of signing up for a similar plan with T-Mobile Jump results in overall charges of $1,422 – a difference of almost $400.

As a reminder, both services allow customers to upgrade their smartphone or cellular tablet early, and in order to make this possible subscribers are placed on a monthly payments scheme. While AT&T is proud to boast that its Next program features no upgrade fee, activation fee, or financing fee, the cost of an iPhone 5 – $120/month with unlimited talk and text, and 3-GB of data – is significantly higher than the cost of purchasing the same handset through T-Mobile Jump ($60 for unlimited talk and text, and 2-GB of data, along with a $10 activation fee).

Despite the $146 downpayment, $10 SIM card fee (applicable to new customers only), and upgrade cost of $145, overall T-Mobile Jump is still more than $400 less expensive than AT&T Next, as outlined in the below image:

AT&T Next vs. T-Mobile Jump.

It should be noted that after the original publication of Consumer Reports’ investigation, AT&T contacted Boy Genius Report with a minor correction:

AT&T writes in to say that ConsumerReports should have also included cheaper AT&T plans, including a plan that’s $110 per month that includes 4GB of data and unlimited text and voice, along with a $90 monthly plan that includes 3GB of data and 450 minutes of voice calls along with unlimited texts. Neither of these plans fully closes the gap with the unlimited voice, text and data plan that T-Mobile is offering, however.

That being said, it looks like T-Mobile chief executive officer John Legere was nevertheless right when he argued that customers pay more, and get less with AT&T Next. For now, at least, subscribers looking to sign up for one of the above plans should consider choosing T-Mobile over AT&T, even if the latter does have a larger (and faster) cellular data network.

Whether Verizon’s own Edge program will offer customers a better deal, however, presently remains to be seen.

We’ll keep you updated with further information as we receive it.

In the meantime, see: Apple Comments On Developer Portal Outage, Promises To Be Back SoonApple Buys HopStop To Add Travel Directions To Maps, and Apple, Samsung Renew Talks To Settle Massive Patent Battle.