I do the Spring tune-ups on two mowers every year. They belong to two owners. last Spring, they came in for their yearly spring tune-up.
One, the deck was very good condition, clean underneath, paint nice, but the other mower was almost ready for the scrap yard. they were both around the same DOM.
The nice deck has been scraped off every year, by the owner, oiled and stored, and is solid. The other one--I scraped off about 3 pounds of caked grass, dirt, dog droppings, and what ever! I could see holes starting in it after i scraped it off. I doubt it will come in this Spring.

Toro 22197. It's is a little pricey, but you get what you pay fro.