I switch between Continental TContact Winter and Nokian many-spikes. Continental are transitional tires so penalty for keeping them on too long is limited. In the other direction I am just unnecessarily slow. In any case, I may swap every few days and at times put a studded just in front. I do the swapping in 2 sweeps. At first I wash the tires and let them stand to dry. After they more or less dried out I change the tires. I use Koolstop/Soma tire levers for taking the tires off and help myself with one or other tire bead jack to put the tires on. Altogether it is a 6min (taking off/washing) + 16min (swapping/putting wheels on) operation. It is not a big deal when you weave it in-between other operations, but in the morning I must of course plan for this not to get late.