[Moto G 2015 Android Development] FNetV1:
Results:

I decided to flash the radio using OP's indicated ratio files for the 5.1.1 version US Sprint, then I rebooted the phone only to discover that I have lost all connectivity. It would connect with an explanation mark on the signal strenth like for 3 seconds and then disconnect. Seeing this I opened up the Partition Backup and Restore app that you recommended and did a full restore for these six partitions "/modem, /modemst1, modemst2, /fsg, /ssd and /carrier". I had to do it one by one, then it said restore succeeded.

I rebooted the phone and now it boot looks to the boot logo and that's it, but I am able to enter to fastboot so restoring what should have been a seamless restoration of these partitions to restore my backed up baseband ended up soft bricking my phone.

At the moment I am trying to mount NON-HLOS.bin on my computer but can't seem to figure out what king of disk image is that, its a .bin format that neither MagicISO nor WinMOUNT can understand, the latter saying it is able to mount .bin images but the backups that I made using Partition Backups and Restore I had saved it as .img that I can mount even with ImDisk Virtual disk successfully.

I dont know if I can flash the .img version directly using fastboot or if it HAS to be a .bin file.

if not, how to I mount R/W the existing NON-HLOS.bin so that I can replace the files internally with the ones inside the backed up .IMG one and then save the bin so that I can fastboot flash it?

Failing all that I suppose I shouldnt have any problems flashing a stock sprint firmware via Fastboot but I am afraid that would leave me with the same results as the one I got by flashing OP's radio for US Sprint, my phone would act as an official Sprint phone, it would have no knowledge that its a Virgin Mobile phone, much less a Data Done Right phone that only work's with Data Done Right's special APN settings.

I guess I might end up with an XT1548 that I might not be able to continue using with my existing DDR plan (I have two $40 unlimited top up cards with me that I purchased a few weeks ago), UNLESS I can find an original stock image that is specifically meant for the Data Done Right variation.

Never knew Data Done Right version of this phone was going to give me this much trouble.

Update: I flashed OP's radio firmware via Fastboot and that made it get out of boot loop. 5.1.1 loaded fine but I have no service. I thought partition restores were supposed to restore a partition 1:1 verbatim, but obviously there was a difference that my phone didn't like when I did the "restore" which caused the boot loop. I will be investigating this.

Update 2: Success I did it: I repeated the restoration procedure using the Partitions backup & restore app, but this time I only restored the following partitions:

/modem

/modemst1

/modemst2 and

/fsg

thats it, I didn't restore the others (/carriers, /sdd, /etc. etc, etc) and then I rebooted the phone. This time it rebooted successfully and yes I am able to connect to 4G LTE again, but still no 3G fall back and that issue is still open and needs to be resolved, possibly it could be a ROM bug? maybe, unfortunately there isn't any other stock based ROM that I could try besides factory stock.