The mokes may be OK but it isn't exactly "safe", Espresso. In the first place, it's about as exposed as you get. In the second place, the book says there's all these anchorages and when you go into them it's 30m and not much further to the shore. Lastly, I anchored there on a protected shore, in the morning it was a lee shore, and the runabout next to me dragged. After a bit of horn-blowing, they got the motor started within jumping distance of the shore.
I just think it's an exaggeration to describe the Mokes as "safe". (as anchorages go)
There are also UNSAFE places that LOOK SAFE. Examples are the far end of Whangaparapara (Gt Barrier), the western end of Jacksons Bay (end of Coromandel), because they have WEED. WEED will make you drag in a blow, unless of course your anchor happens to catch on the bit that Maui dragged up

(South East side of Little Barrier, is also a place where there is lots of WEED which may affect anchoring)
Anyone planning coastal cruising or anchoring should get a copy of the Royal Akarana Coastal Cruising Handbook, available at most stores. Although some of it may be obsolete, or locals may have a better description in their area, it's the ONLY handbook which describes anchorages around NZ (unless there's another one

)
Edit: the UNIVERSAL recommendation for rode-length is 3x depth, extending to perhaps 5 or 6 times whatever in bad conditions. (Per one of the other posts). It is possible to get away with 2x depth with an all-chain rode (though you wouldn't in severe weather). I have no idea why Espresso mentioned "2x". I have "tested" a Rocna anchor (one of the new more secure types) at 2x rode and it DID hold fine on that rode, but only tested in 15kn and I sure as hell wouldnt get any sleep that way. (Rocna claims about twice the holding power of the next-best anchor, I dont know, see their website)