I agree to wait for a bit until the bugs are worked out. I can't speak for the"professional" features for programs like excel, but I used the preview and now have the official version running on El Capt.
While I enjoy the fresh theme/look of office, along with some of their work flows, it is not stable enough to use (and this is coming from someone who always like to play with the latest betas and can put up with some bugs.
With El Capitan:
Outlook is a not go.
Word/Powerpoint are hit and miss for me, depends on the day. Some days can't get it to even start. If you are dependent on these programs, wait until the release a fix.
There is another forum here that has a link to an official Microsoft page where they acknowledge the issues, and say they are working on a fix. I can't seem to find it, but saw it just a few days ago. This is a well documented problem.
I do also agree that I'm not a fan of the way that excel animations/scrolling works. I don't need the box to be animated as it goes from box to box... it takes too long and feels like it is lagging. It was the same effect for the Word cursor, but either they sped it up, or I got used to it.