Muskoka chair vs Muskoka rocker
The classic chair already reclines. The rocker moves instead.
The Muskoka rocker keeps the wide arms and the slatted back but sits the frame on curved runners, so the whole chair rocks. It is a porch chair: it wants a flat, hard floor and a roof. On a lawn, a dock or gravel it does not rock, and on a deck with gaps it can catch.
The classic chair has the recline built into the frame instead — the seat tilts back, the back leans — so it is already the relaxed posture the rocker is trying to reach, and it sits level on anything. It is the one for the dock, the fire pit, the lawn and the deck.
Which to buy
Covered porch with a boarded floor: either, by taste. Anywhere else: the chair.