This April my Q220 caught fire and pretty much destroyed itself. These are some photos that I sent to Weber:
BTW, the grill was on a wood porch when it caught fire. Burning plastic fell on the deck and could easily have torched the deck if we had not caught it in time.
When I contacted Weber, they asked me if I cleaned the regulator (nope) and always checked the external tank connections with soapy water (also nope).
They sent me a bunch of replacement parts, but long story short, I decided to just pitch the grill.
Not sure if I'll buy another Q, but I will
definitely perform preventive maintenance from now on.