Just spent a week skiing the Vialattea, we were based in Sauze d'Oulx.
Positive aspects is the overall great pistes with a lot of variety of black, red and blue runs. We were also lucky with the snow so had plenty of powder off-piste. Skiing was really wonderful. A one week lift pass also includes one day skiing in Montgenevre. The lift pass was also significantly cheaper than last year's lift pass in the Dolomites. The area is rather large, often the only lift queue we had was the one in the morning for the first lift, and then everyone played at different slopes and we didn't have queues. Prices for drinks and food are also very reasonable
The more negative aspects are the slow, old fashioned lifts (at least compared to many Austrian resorts, the Dolomites, or the big French resorts), which tend to stop frequently. There are also not enough facilities, such as toilets, picnic areas or some fun parks in the resort on the Italian side.
I guess you get what you pay for: Skiing is great, the area is large with a lot of variety, but rather old fashioned