My impreza is equipped with X-Ice 2 on very cheap 17inch alloy wheel.
It's a bit scary on very icy road to get rear ended, because it is too easy to drive & you see everyone else sliding like no tomorrow. The EBD along with the ABS system work like a charm.
On the snow it provide decent traction but not to the point of saying they are awesome. you clearly see a huge difference in acceleration compare to FWD cars.
I also changed my wiper with Rain X which perform a tad bit better than the OEM one. The OEM one doesn't seem do add enough pressure to wipe the glass properly. The Wiper De-Icer is mostly useful on snowy day. On very low temperature the wiper work even before the windshield is completely de-iced to a point you can crap out the rubber of your wiper if you don't pay attention of the ice over it.