If you do end up getting winter tires, I would recommend keeping the 189's for those tires. If you sell the 189's, when you go to sell your car, you will need to buy 189's again. While you may get some money back by selling them, you will also pay more switching winter tires on and off your aftermarket wheels. In addition, every time you swap tires on a set of wheels, you are opening yourself up to the tire shop damaging your nice aftermarket wheels.
The other (minor) positive to keeping the stocks is that your car will have two different looks throughout the year instead of one.