I have flown Swiss in business and the service is much better than United. The FAs are much more service oreinted. It doesn't even compare. The food on United is really bad.

Where United shines is with its technology. On Swiss it is much harder to change seats (especially within 48 hrs.) and make changes to reservations. I was in ZRH this summer during thunderstorms and it was pure chaos. Even business class passengers were treated poorly. They seem way behind United when it comes to technology.

If everything runs normally I would pick Swiss as overall they feel more premium for the money.