If there's a pre-established relationship though, then I see no problem with complimenting my coworkers on a new haircut or new shoes or a new jacket or new dress or new earrings or whatever.

It also helps that I am married, everyone knows I am married, and I am an objectively unattractive human being and none of my co-workers would possibly think I am hitting on them because that wouldn't make sense to anyone at all.