Since I have the Zacuto I will only comment on that relocator. It is not too expensive for me because it does the job and there is not a better alternative. The Zacuto will work on any 15mm set of rails from any manufacturer.
The Shape wont work out of the box. It appears you need to have the system to attach it to like their handles and I guess you need to buy your own cable.
The Denz, Arri, and Zacuto units are fine.....they all are available now to slide on 15mm light weight set ups. As for Zacuto being expensive, $320 is expensive?....are you expecting what, $100?...maybe for a bad knock-off from China that fails in a week or two...Denz is some of the finest, ultra light weight, specialized camera accessories one can find. Knowing that, I'd put little weight in some random internet posting by someone I don't know and don't know the qualifications.