They claim to make use of quantum effects -- in an abstract sense, quantum tunnelling across potential peaks in the solution space to access classically unreach

They claim to make use of quantum effects -- in an abstract sense, quantum tunnelling across potential peaks in the solution space to access classically unreachable absolute minima. If that claim is true, then I agree that D-Wave is a type of quantum computer. What is disputed, I believe, is the truth of the claim.