The Ring. Musically very good, you can see why the BPO were keen on Petrenko. Stefan Vinke was a pretty decent Sigfried, the best I've heard on stage. He's coming to the ROH Ring in this role in 2018 apparently, should be a considerable improvement on the previous two here. Catherine Foster I'd heard before in Weimar, perhaps not as comfortable in Bayreuth as in the smaller house but, again, a great improvement over Covent Garden's last Brunhilde.
The production stated out promisingly (Rheingold set in 1970s US, all Pulp Fiction style petty gangsters), but deteriorated. Siegfried received the loudest and most vehement booing I've ever heard in an opera house, a comment on the production, the singers and orchestra got a very enthusiastic response when they took their calls. Being subject to a Marxist theatre director's deliberately incoherent and provocative staging, purposely undermining the great set-pieces, is all part of the modern Bayreuth experience!
Tristan next year perhaps.