Will have to have a look. Could be handy in the winter/rainy days.
In winter or if the car is particularly dirty I would advise a quick trip to the local jet wash (or pressure wash at home) just to blast off any big bits of crud and remove as much as possible to avoid any possible damage.
Gowd I wouldn't!
Pressure washers bash the gritty dirt against the paint to get it off (under pressure). Maybe ok if it's well waxed up and kept so but snow foam far better let it sit on for a few mins then just wash it off with a regular hose. Removes mud/dirt etc, in summer just a chamois off if winter 2 bucket wash.
Each to their own 
I would never use a pressure washer on my car. The jet can fracture paint, allows water to get into places that are designed waterproof, but not anticipating a 120Bar splash of water etc etc.
I do use a pre-wash (VP Citrus) to lubricate and soften the worst of the dirt off before pressure washing(didn't want to get too OCD on here!)
One of the 2 places I live (long story) is an apartment block with no external access to water so an ONR wash is best that can be done. Doing an ONR wash on a particularly dirty car isn't advisable (risk of marks etc) so the best option is to prewash elsewhere (where external water supply is available) to get rid of most of the dirt before using ONR.
Its the only option I have - each to their own with what facilities & equipment they have.
In the other location I live (detached house with external tap) I would do a full 'traditional' snow foam/2BM wash.
I also believe any damage to paintwork from using a pressure washer is down to poor technique of using the tool. If the dirt is well lubricated (prewash) and the PW is used from a safe distance (and pressure adjusted if possible) and the correct movement things will be fine.
