MGMAT -- Good if you like the way they teach

I'm currently enrolled in the full in-person 9-week MGMAT course and all I can say is that the course is very demanding. As you may already know, your GMAT score will inevitably reflect what you put in.

As far as the two courses go, I feel as if Knewton and MGMAT use different teaching methodologies; albeit, both are highly structured ways of prepping. MGMAT is more old-school: here's 10 books, study organizer, stopwatch, now it's up to you. Knewton claims of it's "smarter and revolutionary" way of prepping: adaptive without any traditional resources i.e. books)

So it's ultimately up to what your study habits are. If you're like me who find it hard to self-motivate and self-study, then either prep is ideal. I would suggest that if you're going to spend $1000 then you should aim to get the best of both worlds. Get all the Manhattan guides, OG, OG Quant, OG Verbal (they offer the package on the MGMAT site for like $280?) and also sign up for Knewton $690. Yes, there will be a lot of overlap but I think it's a smart way to reinforce concepts :-D