Done properly, yes. Cheap mesh bags from the supermarket - usually no.
A shoe wash bag does three structural jobs:
- Stops the shoes hitting each other through the cycle
- Protects the drum from the shoes (and the shoes from the drum)
- Protects the shoes from dye transfer - if the bag is the right colour
That last one is where most bags fail. A yellow, green or grey wash bag will eventually transfer dye onto a light-coloured shoe under heat and agitation. The fix is colour fastness testing. The Shoe Wash Kit is built chalk inside and out, tested to ISO 105-C06 grade 4 colour fastness - the standard used to qualify the lining of a high-end garment.
The other failure mode is the zipper. Cheap mesh bags use single-thread zip tape. It opens mid-cycle. Ours uses a concealed self-locking zipper, stress tested to 50 cycles at 60 degrees and 1400 rpm without failure.
Bag colour and zipper construction are the two specs to check before buying any shoe wash bag.