I tried 30 day shred, didnt find it "brutal" i though it was a bit on the easier side of things. Having said that I had just tried p90x with my boyfriend and it was next to impossible for me to finish most of the work outs. I have found a happy medium in Chalean Xtreme. Its challenging and its working for me so thats a plus. The only thing that would put me off other work out dvds is the repetitive workouts, with chalean xtreme and p90x its a different routine every day of the week and then it changes up every 30 days, which is great for me cos I am easily bored, and apparently there's science behind why they do it like that, keeping your body guessing so you're getting the most out of it or something like that.
Keep us posted tho and let us know how you're going. Also if you can find chalean xtreme you should totally give it a try.