We have done it and if you have time it is great. We usually cross using the Channel Tunnel and overnight 3 hours into France giving us 6 hours of travel to the resort the following day.
The roads are exceptional and all you need are some snow chains which to be honest are rarely used. Order your snow chains from Amazon, we like the snow socks, they are fabric and easy to put on.
We have not done this but we know a lot of people that do. Bourg St Maurice is the nearest Eurostar station.
Onward options to the resort:
Around 65 minutes; Adults 12€, Youth (U26) 9.50€ (www.altibus.com).
Around 35-50 minutes; about 50€, depending on the size of the taxi.
Depending on where you live there are a number of flight options:
2hr | 142km
2hr45 | 223km
2hr45 | 219km
2hr50 | 221km
From the airport to the resort you have a couple of options:
Rent a car - We now tend to rent a car, it is a leisurely drive to the resort and gives you some added freedom and flexibility once you are there.
Book a transfer – There are lots of transfer companies varying in price, all offer return travel from the airport for round 120€.