How important is it to replace a defective VCV?
 

I'm pretty sure that, on my 91 300D, I have a defective vacuum control valve. As I have neither the patience nor fine motor skills to attempt Sixto's R&R (PeachPartsWiki: Anatomy of a Transmission Vacuum Control Valve) nor the desire to drop $493 on a new one, I'm wondering what the risks are simply living with it as is. Only symptoms are mild shift bumps at low speeds and difficulty in retracting the headrests. I suppose that potential concerns are the extra strain on the pump and the long-term effects of those shift bumps.

Thoughts?