Is UA notorious for bad international flights? I used them to Paris and back last fall without issue. I lucked out and selected a non "Economy-plus" row online, but it turned out to be it anyway without the charge
Yeah I would avoid UA at all costs, lots of bad experiences when I was younger, only time I've flown them since was for interviews when companies paid for my flights.
I've had several very average experiences from SFO to various spots in Europe in UA business class and first class. So, I now try and redeem miles by using their affiliates. The last time to London from SFO they flew us to LA and then non-stop to Heathrow on Air New Zealand Business Class. It was flawless service. Previously we made connecting flights to Paris and Rome through Luftansa using AU milage. The service was fantastic.