Like you, I've never seen the 15yo here, only the 17yo. Here's my notes:
Score (85) Glenfarclas 17yo 43% abv (Speyside)
Color: Honey gold sunset
Nose: Honey, coconut, butter, graham cracker, dried fruit, polished oak, orange zest, almond paste
Palate: Fiery, lightly sweet malt like the 12, but rounder, cedar-y, watery, fades fast
Body: Thin, warming, biting
Finish: Long vapor, smoothing out to infinity, feels more than 43%
Notes: A lot like the 12, but with a more refined, smoother finish, just not quite as complex as I was hoping. I will revisit after awhile, but probably not going to be a favorite at these prices. If the 105 disappoints I’ll drop this as a distillery that’s just not my style. Revise: Getting richer already, up two points. The complexity of the nose has grown and the palate sweeter, slightly mellowed.
Quote: Above average and gaining
Since these notes I've also tried the 105, 25yo, and have an unopened 21yo, so you could say this is a substantially worthy distillery to explore.