I love this trimmer - easy to use and cuts true every time. There were no instructions in the box about where to insert the batteries, or in what direction, but after hunting around, I finally found the battery storage and after trial and error, got them loaded in correctly. The guide light is a great help, although it would be nice if it had an on/off which because if you leave the guide down, the light stays on and would drain the batteries. I just have to remember to leave the cutting guide in the UP position when I'm not cutting.
Overall, it's a fantastic tool.
As another reviewer stated, it takes a bit of practice. BUT once mastered, this trimmer ROCKS! I can trim off very small bits from my photos/papers or cut 12 x 12 sheets for cards with absolute accuracy. Have used for about a year now and only replaced blade once. Blades are cheap. The light helps see exactly where the blade will cut. This is my favorite trimmer by far and I've had a LOT!