The argument often put forward for consensus, that it respects the freedom of the participants in a group by not forcing them to agree to a decision which they reject, makes little sense to me. So long as a group is formed on the basis of free association a member always has the option to quit if a decision abrogates their principles, thus whatever its flaws may be, majoritarian voting is not a threat to freedom.
A much better argument for consensus and against majoritarian decision making is as follows. Consider a group of activists that chooses to use majoritarian voting, not consensus, if highly controversial decisions are pushed through by majority without compromise that group will tend to suffer- conflicts intensify, splits become likely, and participants in the minority feel no ownership over decisions they did not contribute to. This is the kernel of truth that consensus decision making recognises and the best argument for consensus.
This argument gives us reason to consider using consensus. Pretty good reason I would think. But there are a bevy of arguments against consensus. For example, that it can water down decisions so that no one ends up happy and clear action is never taken. Sometimes for the sake of reaching compromise and not holding things up it can make participants agree to more than the feel comfortable agreeing with, where a straight up vote would at least allow for the clear articulation of dissent.
The sum of these arguments and counter-arguments is indecisive, there are good reasons you might feel attracted to consensus, and there are reasons you might be repelled. This leads to interminable debates about the strengths and weaknesses of consensus decision making on the left.
I think that the problem is that these argument typically treat consensus or majority voting (whichever is preferred) as untouchable and inviolate. Decision making processes (so long as they respect the basic principles of democracy and equal power or isocrachy) should be regarded as strategic choices, and not choices of principle. Anyone can leave a voluntary group, no one is forced to participate in whatever decision making structure is created, so there is nothing wrong with a diversity of decision making structures being used in a diversity of groups and situations. Some decision making procedures might be so odious that they should never be adopted, but neither consensus nor majority decision making, nor the various compromises between them, strike me as so. A better principle in keeping with anarchism than either universal majority voting or universal consensus then, is diversity of decision making.
If we move beyond treating consensus and its alternatives as absolute principles, a wealth of options and points to think about are opened up. Strategic factors to take into consideration when picking a decision making structure include the ideological diversity of the group, the interactions of different personalities and tendencies, the size of the group and the speed with which decisions must be made. The options on the table include, but are not limited to, majority voting, full consensus, consensus with a fall-back vote, seventy five percent consensus and consensus for certain types of issues with majority voting for others.