I can’t say I’ve heard any of those ARC class D amps, so why not ask AI? To my thoughtful query, "were audio research class D amps garbage?" it responded thusly:
Early Audio Research Corporation (ARC) Class D amplifiers, particularly the 300.2 and early DS series, were not universally considered "garbage," but they faced significant criticism for lacking the warmth, depth, and musicality typical of ARC’s tube legacy. While some reviewers found models like the DS450 to have "natural clarity," many audiophiles found early high-end Class D to be dry, harsh, or fatiguing compared to Class AB.
Initial Perception: Early, lower-end Class D, in general, suffered from high distortion and harsh sound, leading to a negative reputation.
They’re probably inexpensive for a reason.

