A heart valve therapy system including a delivery device and a stented valve. The delivery device includes an outer sheath, an inner shaft, an optional hub assembly, and a plurality of tethers. In a delivery state, a stent frame of the prosthesis is crimped over the inner shaft and maintained in a compressed condition by the outer sheath. The tethers are connected to the stent frame. In a partial deployment state, the outer sheath is at least partially withdrawn, allowing the stent frame to self-expand. Tension in the tethers prevents the stent frame from rapidly expanding and optionally allowing recapture. Upon completion of the stent frame expansion, the tethers are withdrawn.