I'm always amazed at how good it is.
I don't always need it and like to leave it like this for 12 months.
It still has enough to wash my wetsuit or wash my bike.

The battery lasts really well, I have the big tank 8L and so maybe half is gone or less. Never had problems with the battery, more with water.

Depends on which bike you want to wash and how dirty the bike is ;-) But for a very muddy/dirty bike, the battery lasts easily. I would rather recommend an extra canister of water :-)