I just came back from a week long sleddin vacation with by buddies in that same area (19 Jan - 27 Jan) - the trails are amazing.
All these area we rode in had about 1 1/2 feet of hard packed with 1 1/2 to as much as 2 1/2 feet of loose stuff on the sides.
Valcourt, Acton Vale, Compton,Cooticook, Sayerville, East Hereford, sherbrook, Magoog, Bromptonville, Waterloo, Norton (VT), Beachfalls (VT) All these places have great snow.
There is a small problem however with the small streams in the woods that are not frozen yet - but the local trail people have cut down some small evergreens to fill them.
P.S. If you don't ride Ski-Doo in Valcourt people look at you very strangly - I rode my XCR and got strange looks from all the folks. I love town pride like that.