Sorry, OP, I gotta throw my pennies in the bucket...
I have a Summa, and I like it better than Roland. I always had problems getting the Roland to track straight (The guy that owns it could load it straight most of the time). Also had problems with it when it had 50 yard rolls of material, you had to roll the material out, or when it reached the end, would "snag" and you'd end up loosing that run. (The machine was about 7 years old, and was a Camm-1. I don't know if the new ones are any better)
all ROLANDS are CAMM-1. i started with a PNC-1000. 15-20" cutter. bad on aliginment, if you dont set it right to begin with. i did 20 ft runs with it, when needed. i moved up to PNC-1100, have 2 of these. 24", tracking was better, but still had to line up right to start.
i now have a CX-300 and its great. STILL need to line up properly, and it will feed page size, then go back to begining and cut.
and with all these since 93, ive cut from corel, and nothing else. i never used a summa or graphtec, so i can say anything about em, but i belive SUMMA , has a driver that will also cut DIRECT FROM COREL.