This is a new release from Kittling Ridge Estate Distillery, makers of Barrel Select (part of the Forty Creek line) and Pure Gold. The distillery also made Three Grain but it seems to have been withdrawn (perhaps to make room for Canadian Mountain Rock Whisky (the full name)).
Mountain Rock states on the label it is "smooth, gutsy and flavourful". That covers all the bases. There is no age statement, and the proof is a standard 40% ABV.
The nose seems light with a whiff of grain ethanol. The taste is fruity, grainy, with some oak and chestnut-like depth and a touch of sweetness. The ethanol tags along and dominates the finish. Although the label states that "heavy char oak barrels" are used there is little bourbon-like oak char taste, maybe the barrels are reused (a common practice for Canadian whisky).
This is a good product and good value for the $22.45 (CAN) being asked in Ontario. The name and label design suggest to me the target audience is the younger crowd, say 21-35, not the single malt-type crowd.
I am getting hints of Three Grain in the whisky, Three Grain has a distinctive sherry background. I think there may be some Barrel Select too. Possibly those two are being blended with Pure Gold to pick up the latter's mild, standard-type palate. Maybe Mountain Rock is a purpose-made blend finished in sherry casks. However it is made, the result is good and offers more taste than most Canadian whisky.
From the point of view of finesse and complexity I prefer Wiser's Reserve (Special Edition) 43% ABV and second to that, Danfield's Private Reserve. Crown Royal's line up is good too.