LPG system

When it came to the LPG side of things, I looked at standard bottles, small & medium, looked at having a tank fitted under the van and then finally decided on the refillable bottle from Safefill. The first choice comes with a heavy bottle to start with and then I thought, if faced with wild camping in scotland for example, and I had a half used bottle, do I risk running out, or do I give a bottle back half full just to make sure I have enough?
Second one was attractive but when I looked into price etc, it didn't compare to the safefill system. £149, and if I only need 5 ltrs to fill it up, call at a garage and only pay for what you need.
Used hob and heating several times on the isle of man maiden voyage trip and I'm over the moon, it doesn't even seem to have moved.

Oh, by the way, I understand you should have a drop vent in the cupboard with the bottle, so I put two in.I tried to make it as airtight as I could and have also bought a carbon monoxide and smoke alarm and fitted them. I have also fitted a fire extinguisher and first aid kit and put them all close by the door. We actually remove the bottle and fill it away from the vehicle, just in case.