Swap stock 20's for small diameter wheel with winter tires?

[jmbones]

2011 Murano LE - stock tires 235-55-20.

With the low selection of available 20" true winter tires (studdable), has anyone thought about swapping the stock 20" wheels for a smaller diameter cheap set of aluminum or steel wheels to mount winter tires to for winter only? The overall size would basically be equivilant to the 20" because the tire sidewall would be taller. The initial investment would be a little high because of the new wheels and TPMS sensors but I like to have a winter set and normal set. This also saves on the road salt eating up the factory 20's.