Have taken AF from SFO and found it surprisingly comfortable and the crew more congenial than on AF flights from the East Coast. Have taken BA from Seattle is regular economy and yep, it was cramped and uncomfortable, but the entertaintment systems will help pass the time. Since then my transatlantic flights with BA have been on premium economy or business, thankfully.
Re the BA seatback entertainment systems, one warning: Do NOT watch I, Robot. It's jinxed! I made four attempts to watch it coming and going on the most recent trip and within five minutes of each attempt, we hit strong turbulence. The turbulence dissipated shortly after changing channels (and thus I watched Troy in its entirety three times).

Troy three times? You poor dear.

For what it's worth, I just booked a flight to Italy on Lufthansa through Star Alliance, using USAirways FF miles. The route is SF through Munich, with a plane change to Italy.
I've phoned Lufthansa twice, once to check confirm that the reservation was actually in their system (it was made by USAirways) and once for a seat assignment. Each time, the person answering the phone was so unbeliveably customer-friendly that I almost burst into tears of gratitude. They both seemed as if they were very eager to meet my travel needs. This is in stark contrast to most (not all) USAirways personnel that I spoke with who seemed as if they just wanted me to go away. I am not a "high maintainance" customer, by the way. If their phone mentality foreshadows the flight experience, I'd encourage you book with LH, if their fare and schedule permit. I have absolutely no connection to LH.

Betsy - did they give you a seat assignment? Have heard LH will not preassign star alliance FF seats until last minute, so they are often in the rear & middle. Don't know if this is true or not. Also, how far ahead did you book for?

My cousin who until last year flew to Munich three times a year always took Lufthansa (from SFO) and raved about them.

And if you want to meet a high maintenance gal she is the one, LOL!
Not an easy person to please.

Absolutely no problem with obtaining seat assignments. The return trip is on United, but LH could assign that seat too. Lovely rep bent over backwards to make sure the seats were perfect for me, then she offered to arrange one of their special meals and asked if I needed to rent a car. She was very professional, but warm. and seemed unhurried. Amazing!