I think it depends on the application you want to do if a summa is just "nice to have" or "urgently needed". Summa have - depending on the model - some features which are second to none on the market:
Tangential knife: Currently Summa is the only producer of roll cutting plotters who offers a model with true tangential driven knife. This have advantages in several ways, for example with thicker media.
OPOS X: the Summa OPOS contour cutting system can use up to 128 markers to improve accuracy in difficult situations, it can compensate an eventual media bowing (smiley) effect with OPOS XY, it can do completely automatic batch contour cutting with using OPOS Barcode, it makes contour cutting of multiple copies of the same sheet really easy with OPOS SHEET MODE, and should improve accuracy on long tracks with using OPOS PANNELING. By the way the marker recognition is one of the most reliable on the market since they use a white light sensor. I know roland contour cutting well, and the Roland Quadralign in comparison to the Summa OPOS is much slower, much more difficult to calibrate and much more unreliable in marker recognition.
There are some other accessories not available on other plotters: OPOS-CAM camera-based contour cutting system (not the same functionality as the other, but really speedy), a take-up unit for cutting long jobs or multiple jobs and so on.
On cause because I like Summa very much is that I work at a summa dealer and been a summa supporter for nearly 17 years now
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