We’ve had these for a year and have kept them for heating emergencies. We live full-time in an RV and have settled down. There’s no reason to keep them anymore. We don’t use propane for grilling.
They’re not the prettiest (the plastic is faded) or the newest, but we’ve never used them. They’ve either been in the back of the truck or stowed under the rig. The only direct exposure to weather has been in the back of the truck while traveling. Otherwise, they’ve been under cover.
The blue plastic seals have not been broken.
Propane never goes bad if kept in a properly sealed container. If they weren’t well-sealed we would have smelled them by now.