Avgas is actually wonderful stuff, the quality stuff in fact when compared with whatever else you might be burning. I left some sitting for three years once and had no problems with it - it was seemingly good as new, not withstanding the recommendation to use it after a year. I also drained the 100LL from a tank once and two days later hid it behind a couch in the living room to store for a period - with no smell whatsoever evident because it leaves no residue. Try that with auto fuel or (yeeeech) diesel.
Meanwhile if I accidentally leave any of my 'fleet' sitting with the horrendous alcohol, toluene and benzene stuff they call auto fuel in 2014, it gells, clogs everything in sight and takes time to fix. I spent three hours last weekend cleaning the pilot jets on one of my motorcycles after two months storage... which is really not how I like to spend my weekends!
Ergo, I love Avgas
