A lot of whether a bag will survive the top-loading washing machine agitator depends on how lightweight it is--the lighter the bag, the more delicate the internal baffles. I would never put my WM Ultralight in a top-loader! Even small towns have commercial laundromats that have at least one larger size front-loading machine.

Bob, I've successfully washed down items (not my sleeping bag, yet, though--just pillows and comforters) and had them fluff up to their original loft. It takes forever to dry them, and you have to keep stopping to break up all the clumps. 2-3 tennis balls in the dryer help with this, but you still have to do some de-clumping by hand.

I'm lucky in that my lovely daughter-in-law has an extra-large front-loading washer and extra-large dryer. I will be up there for a week in March and will wash my beloved WM bag then.