Before the scoffing starts let me say that I think using a person as an editor is better than using a set of algorithms, if for no other reason than it puts a fresh set of trained eyes on a manuscript. StyleWriter, Prowriter, and others are out there and they find mistakes, make suggestions, and might be a good answer for the first few rounds. Any comments of a general nature or specific comments on a particular package?
After a rough draft I run through Hemingway editor just to pick up anything egregious and tidy up. Doesn't replace a human editor though and hates complex sentences trying to make me use baby sentences at times. Great for the first round of proof reading though.