I've had both and prefer the Glendronach, but to be fair, Glendronach IS my favorite distillery. Their 15 Y.O. "Revival" (which I'm hoping makes a return) is my all time favorite Scotch, and their Cask Strength releases are invariably amazing.
Glenmorangie Quinta Ruban is a port cask that at about $40 is an absolute steal & terrific dram. Virtually ANYTHING from Benriach, if you can find it (we stopped getting them here) will be amazing, but their Tawny Port Cask is a huge favorite. They have a 15 Y.O. Dark Rum Cask that's really good too, and all of these are under $100.
For a dessert Scotch I like Arran Malt Amarone Cask. It's under $60.
~Boar