I have experienced the cut not being accurate by putting it through straight. Especially the 5" square.
To know if you have a problem, cut some fabric both ways, and measure them. I was off 1/8 of an inch, (shorter on one side), which, sewn many times over in a quilt will make a huge difference. I called Accuquilt, and they told me to always put the dies through on an angle. Sometimes, that's hard to do, when you have a lot of fabric trailing behind.