good for you,
i have not had that good of luck with my air tank,
craftsman 33 gal tank, Horizontal model
I drained the tank from time to time, but i guess not enough as this summer it finally rusted through the bottom and i had to get a new tank,
but luck was with me, a friend had an old craftsman air compressor that many years ago the compressor threw a rod and it had been setting in the back of his barn for years. told him about my problem and he gave me the old air compressor with the understand that is was not to come home.
all the fittings worked perfect with my air compressor and his tank was still good.
unit is in the shop as we speak holding 90 psi of air ready for the next job.
lucked out on that one as i had looked for a replacement tank for a while.