Heya, I'm one of the many that have tried and consistently use 30 Day Shred. I think it's intense, but the improvements for me came pretty quickly. You'll notice a change in your endurance (and measurements) within the first week or so, if you're anything like me. I do the Shred every other day; I would just get too bored with it doing it every single day. I highly recommend it. I like that I can burn a slew of calories in about 30 minutes and it definitely goes by fast. Good luck to you and welcome to your fitness journey.
Let us know how it goes.