Further to my previous 2 posts re Mexico I am looking at hotels in Mexico city now and also got a Mexico Rough Guide out from the library and in it they have dedicated a whole page to the dangers of Mexico City - oh dear, oh dear! Previously we always left our passports in our hotel room (of course) but generally travelled on the metro, and had our bank cards with us (btw, is Mexico a very cash country, I don't remember).
We stayed at NH Reforma Hotel Zona Rosa the last time, reviews say it is very noisy but near to good places to eat etc. Can anyone tell us where is a good area, but relatively central, not too noisy? Don't mind paying a bit more

Credit cards are becoming more widely accepted these days except for in markets & street food vendors. Be watchful for pickpockets on the metro. I even had one once try his luck in my front pocket. Generally, a good quiet area is Roma Norte/Condesa, with tons of restaurants & cafe's. The anti-tourism protests in the area was pretty much a one-off event. So far. We typically stay at the moderately priced Stanza in Roma. Never was a fan of Zona rosa. If you'll be in cdmx twice on your trip, consider staying in Roma on one leg and the historic center on the other. More hotel options in Centro.

I like the historic center though I can't describe it as quiet. It's mush more user friendly than it was say twenty years ago. If you haven't seen the major sites in the area, the National Palace, Cathedral and Templo Major and its museum, you'll find enough to do for a few days. The Zocalo itself makes for grand people-watching. Last time I was there we stayed at the Gran Hotel Ciudad de México which is quite nice. Plenty of less expensive places nearby -- the Hotel Majestic has great views (and noise) from the Zocalo, and a decent top floor bar (restaurant is so-so). Rooms in need of a facelift.

We have stayed at the Stanza mentioned above. Great location, Nice hotel, a little bland perhaps. Plenty of eating places and bar around and convenient for the metro. We also sat in an NH hotel near the Zocalo. Close by lots of things to see but it was not my favourite part of the city and seemed dead at night and close to some dodgy areas. Last year we stayed at NanaVida a very nice place in a quiet area yet with lots of good restaurants close by.

We didn't find the city at all unsafe. Pickpocketing seemed no more of an issue than here at home in central London and we walked teh streets at night with no qualms. We just observed the usual precautions we would anywhere. We used the subway a lot on our first visit but last year we used Uber almost exclusively. Another area I would consider if we return would be Coyacan which we like a lot (though I don't think it is especially central).

Thanks for getting back to me guys, I'll look into your suggestions