I think, if you put this into perspective, the conclusion in simple. The RIVA did a study in 2005 and found that there were 8.9 Million rigs in the US...I suspect that this number has gone up. This does not include Canada, Europe, British Isles, etc. I think the risk of an explosion while fueling up with the propane on is so low I am surprised that there is even a conversation on this topic...I relegate it to the same category of the widow selling a chevy for $500.00 and finding that it is a mint split window stingray.. If there becomes any sort of trend I will revisit this issue..
I agree with 2oldman.. do what ever tows your rv...