I just switched from a Nexus 4G to the Galaxy S3. Over the last day and a half since the switch my data has been dropping in and out (mostly out) I called Sprint 3 times and reprovisioned the device but each time data would fail again after about an hour. Today I went through the same process with another CSR and we couldn't get data working. He then looked and saw a service bulletin for Flagstaff (where I live) for work being done on the towers for LTE conversion. I wonder if he was blowing smoke, or if this is actually true.
For the record the error I get is the classic Error #67: Registration Failure, and when attempting to Update PRL or Profile I get an immediate data failure message. I can do a ##DATA# and get it running temporarily but it always fails again after an hour or so.