THIS is how bread slicers should be, and I don't know why it's taken so long. Or anyway, I've never seen it until now.
I've tried every kind of bread slicer for my homemade bread and loaves from the bakery. I'm completely inept when it comes to making even slices, even with slotted knife guides and those bread knives with an extra strip to keep you from going off track. Guess what, I can go off track.
This horizontal system is compact, easy to clean, foolproof even for a fool like me, and is nothing to set up. Bring your own knife. Then tap that knife against the inside track when you're done and a magnet will hold it in place.
I love this thing.