I've recently had a chance to work with a new editor. Don't know if it will come to anything, and for that reason not going to say who, or what the work related to.
What I will say is there will be a raft of writers out there who'll scream 'you must be mad' when I dare whisper that I like editors. You can learn so much from a good editor (if you can be bothered). I admit, as in everything to do with this business, there are good ones and bad ones, but I've yet to meet an editor who wasn't able to add something to what we were working on.
I see editors as being a vital part of what we do as writers. Its part of the process: another pair of eyes to look over the story, the lack of the emotional connection, the market/business awareness, getting the 'house style' into place. I suppose there are writers out there who don't need an editor, but there are many more who don't think they do.
For me, I know the value of a good editor. I'm just starting out and I'll take any help I can get. My first editor, Steve Haynes, made a huge difference to my first novel, Aphrodite's Dawn, and a chap by the name of AJ French who edited/published two of my short stories (under my alter ego) was great too.
Hope I get to work some more with this 'new' person.