[88Racing]

My turn!

Nope don't like them unless exclusively ran at race tracks that are asphalt/concrete.
Pros:
Great in no to very little dust conditions.
The person doing the cleaning and oiling knows what they are doing.
Great on carburated race vehicles.

Cons:
Dusty dirty conditions plug them up quicker even with foam prebreather.
Over oiled the oil goes everywhere and collects and plugs with even more particles.
Under oiled more dirt into the engine.
To much hype!
Need to be fussy with their maintenance.
Around wet conditions rain sock should be used.

Stick with the paper or the "washable" dry type gauze. Dry types are cheaper and last just as long.

Lars