MrsLugz and me have done a few of these
Insanity is exactly that. Proper hard work if you go all out. 5 days a week for an hour, handy plan to keep tabs on yourself. The diet is pretty strict, but well varied and enough to keep you going. I lost a load of weight and almost got a six pack.
You will find yourself muttering Shaun T’s catchphrases 🙂
T25 is a shorter, more laid back version. Still not easy.
Hip Hop abs is loads cheaper, half hour workouts more like a dance session.
Much better to do it as a team, even if the neighbours do think you’re mental. (we have no blinds in our conservatory.)