I like all itrain cardio, including the icycles. I especially love the ones with intervals off the machines - iBiClimb, iCircuit Circus. I also enjoy doing the iTread Ballets. Pretending the treadmill rail is a barre is a lot of fun. The looks I get in the gym are even more fun.
For straight cardio the first iTri (Set 8) is a great 70 minute workout with treadmill, elliptical and cycle segments.
The recent iTread (Set 25) by Nick was wonderful too. I never expected to like it so much. Nick does not give speed guidelines like Grace, he uses 1-10 scale. His iTread is a blast. 30 minutes with 4 minute intervals of running / hill walking / side stepping with 1 min recoveries.
My favorites among the iTrain gang are Grace and Keith too.
~* Vrinda *~