Based on my, fairly limited, true, experience, option 1 is good for cars where new tank is just not available. Then you are bound to remove rust and coat, etc. If only any type of replacement tank is available (and here you have 2 options), I would just replace tank. What it boils down to is budget considerations.
Flower pot or not - Dansk works, I heard it from so many Members, no doubt there, I think.