AF option
I went this way last summer (to burn some Flying Poo miles) and went Manchester - Paris - SFO. The very old and tatty 747 for the long leg was a disgrace, no video on demand, films in French, and a soundtrack so poor you couldn't hear it anyway (even if you spoke French).
It did however get us to SFO in one long hop, with no internal connections. Coming back was a codeshare from SFo - Cincinnatti - Paris manchester, with Delta, which I have to say, for a US carrier was very good (on the transatlantic sector) but having just flown in from Hawaii it was one hell of a journey with overnight - day - overnight - day flights back to back. Never again !