Turbotax partners with Sprintax. What does that mean?

As TurboTax does not support Form 1040NR,  you cannot file that with TurboTax.  However, we have a partnership with Sprintax who offers filing solution to our TurboTax customers.  See Visit the TurboTax/Sprintax site.

This doesn't really answer the question. If you have paid for TurboTax, do you get a discount on Sprintax? If not, then you are indeed *redirecting* users to Sprintax, and there is not a partnership. Please clarify. Sprintax asks for an Access Code at checkout.

SprinTax and J1 Summer Tax Back are pretty similar, I have used them both and got good results even though J1 Summer Tax Back is a bit cheaper.