On the plus side, there can only be room for improvement - Shaun T you rock!
To anyone that is considering 'Insanity' but feel they won't be able to do it or that they're too overweight to do it I recommend giving it a go. Realistically I am 5 stone overweight (70lbs) and yes it is hard especially with asthma thrown in the mix, but I cannot tell you the sense of achievement you feel after each workout. Even when you have a rubbish workout and feel that you could have done better it doesn't put you off, in fact it makes you more determined to nail it the next time. I'm struggling with the workout at the moment but so is my daughter who is 20 years younger than me and extremely slim so it's not ageist, sexist nor weightist, you get out of it what you put into it and as you get fitter you'll be amazed by what you can achieve - moves that seemed impossible when you first started are suddenly much easier.
And if you're one of those people that hate home workouts because they're boring (as am I) then prepared to be addicted to this one.
Go for it!