We've been using Display Suite with Node displays on one of our latest sites. It was an experiment, and possibly not something we'll do again - DS offers some great functionality with build modes and ways to re-arrange fields and all sorts on nodes, but since we end up theming most nodes quite a lot anyway, it's not worth the extra hassle that Display Suite can add when you want to change the theming on DS fields, layouts, change the fields' settings etc...
We use update hooks to change most things on sites for clients, since this allows us to...