Last night we had the first snow of the winter, it's about time to put the snow tires on, I am also thinking about some other ways to enhance my 400E's drivability on snow/ice. For those who have tried, how effective is it to put sand bags in the trunk? how much weight should I put?

__________________
99 BMW 540i 6-speed 110K Km
03 SAAB 9-5 wagon 80K Km
92 400E (Sold) 245K km
Still missing the days with the Benz, it kept me busy.