I did call suburban propane and just like the forums:) The answers are varied. Their suggestion was just to take it into a local Suburban Propane office to have it looked at. They said that they thought all horizontal tanks were grand fathered, but they said there were some exclusions or "maybe's" here and there.
A simple re certification was 15$, but depending on if, and or what kind of valve she said the total cost could go up to 90$.
I'll call an amerigas and get their thoughts, and probably take it in to be looked at soon.
later
C