Hiflofiltro is a maker of oil and air filters for both OEM and aftermarket, including K&N's motorcycle oil filters. Hiflo also has their HF138 oil filter for our bikes.
Hiflofiltro Oilfilters & Airfilters: About us
They are now distributing in the U.S. their air filters for Stroms. The filters appear to be very good quality. They're following Suzuki's lead by omitting a gasket on their #HFA3611 filter listed for the models up to 2006, $26, (you MUST reuse your old gasket), and including a gasket with the #HFA3614 filter listed for the 2007 & later models, $30. Same filter, $4 for the gasket.
The filters fits fine and seems to work just like any new filter should work. I got mine at my local indie shop.