I have the digitone and the cycles and I have to say I spend more time with the cycles. The immediacy of the cycles is great, and the ability to quickly do drum tracks and melodies. With the digitone all that is possible, and it technically has more voices, but you have to adjust everything to use all those voices. having 6 sequencing channels is quite nice compared to the on the digitone.
I also really like the sound design that went into the machines on the model:cycles. The fact that all the knobs have similar effect on the different machines means that when you control all and change everything it all changes similarly, which is not the case with the digitone. With the digitone and control all you can quickly make a bass drum no longer sound like a bass drum.
I think they are an amazing pair though. The percussive ability of the cycles and the harmonic and melodic capability of the digitone works really well together, and they have a cohesive sound. You have to like that FM sound, but it is cohesive.