I know this is an old ticket, but I thought I would point out the two biggest differences that I've noticed.
Firstly, the bands. Verizon has SEVERELY restricted the radio to the following frequences:
LTE: 13(700), 4(1700/2100 AWS), 2(1900 PCS), 3(1800), 7(2600), LTE CA 13+4 (10+10)
...and then T-Mobile:
LTE: 1(2100), 2(1900 PCS), 3(1800), 4(1700/2100 AWS), 5(800 CLR), 7(2600), 8(900), 12(700), 20(800 EUDD, not SMR)
So essentially, the Verizon Note 5 may have some compatibility with other carriers because of band 4 and band 2, but Verizon's band 5 is missing from the picture. What happens when Verizon starts refarming that?
Additionally, as stated earlier the bootloader is locked. Samsung Knox #FTW. Rooting your phone turns it into a really pretty looking paper weight. This is not the case for the carriers.
Hope this sheds some light on things.