I've finally figured it out!!!!!
I was about to drive back to the Microsoft store and just start using the lumia 950 I bough (which I am now selling along with a brand new sealed dock)...
1. Use WDRT
2. LEAVE SIM AND SD CARD OUT.
3. Install everything using your MSFT account and set up the phone the way you want. Do all the updates.
4. Once completely happy with the way its set up, insert sim and sd card.
I haven't had a singe reboot, or a singe sd disconnect. I purposely restarted the phone over and over (which would have resulted in constant reboots earlier) and not a single boot loop!! I am keeping this bad boy now.
This is my fix and I am certain now, that with the sd card in the phone during the initial setup and updates, some chunks of programs or system files were somehow being written to the sd card resulting in a corrupted file system, possibly something to do with indexing.
Hope this works for other experiencing this issue!