Knight can get some great approvals, but i'd recommend always sending it to someone else who works a bit faster. I'll send a deal to Knight, and by the time they send me their "we received your submission..." email, I've already gotten offers or declines from most of the other people I've sent it too. I'm a big fan of Platinum personally. Quick, efficient, and they can get you some great approvals. Accord and Everest are also great in my book. I have experience with both of them revising offers substantially after some negotiating.