If Ralston can play a bit of TE and in-line block reasonably well, you roll with the younger, cheaper, more versatile player. IIRC, there weren't many tears shed when the WFT moved on from Sprinkle. Keep a TE like Eubanks or McKeon on the PS to move up if needed if Ralston isn't cutting it at TE or one of the other two can't play.

There's a good chance Sprinkle doesn't get claimed off waivers or signed elsewhere after final cuts. You can re-sign him or find equivalent talent off the street if need be.