Called Sprint in my quest to find out if they will be getting 32/64GB S4's and although I did not find out about the S4's (the manager I spoke to simply had no information on that) he did tell me that the S4 MEGA is confirmed for Release Later this Year and that he did not know the specs, but said hopefully it will have better Memory Options from the get go, also e-mailled me this Sprint News Article.
Sprint to Bring Unlimited Data Experience to Samsung Galaxy Mega | Sprint Newsroom
Although it only has a 720P screen and I'd still Prefer to have a 64GB Version of the S4 I would be willing to settle for this if the internal memory is larger than 16 GB (Preferably 64GB).