Turret upgrade worth it on the PT-91 Twardy?

Finishing up the Wilk now with the current on track event. Just noticed that the turret upgrade on the Twardy goes from the T-72M2 Wilk turret to the PT-91 Twardy turret (as opposed to what we spnoften see in CW, which is just [tank name] mk 1 -> mk 2). Does anyone know if the turret gives anything other than the stated HP, vision, and rotation buffs? Does it change shape or armor? I just can't see it without spending 2.2 million silver. If it doesn't change armor or shape, then I'll pass on getting the turret upgrade, since the T-72M2 turret is working just fine for me on the previous tank.