You can take a 925 to any T-Mo MVNO without unlocking... I use Spot Mobile ($39.99 unlimited talk, text and data with 1GB HSPA+42) and love it. I grabbed a free SIM for them from 4gfastdata.com and saved like $10 and got free shipping.
Other MVNO's that work with it off the top of my head - again without unlocking - Simple Mobile (LTE on $50 and $60 plans), Walmart Family, Straight Talk (T-Mo SIM), Brightspot (Target), GIV, GoSmart, PTel, Net10 (T-Mo SIM), ReadySIM and Solavei.
I love the service from Spot but Straight Talk and Net10 offer a slightly better data plan cost. Simple is the only one that is offering full LTE speeds for their plans since 35orLess is gone now. Other than that, you can't miss with any of these prepaid offerings, though watch for ones that that are really post paid - like Solavei and Brightspot as this will add 15-20% to your costs every month.