It only takes one night of restless sleep due to an uncomfortable mattress before you’ll want to replace it. Unfortunately, no matter how much you spend on your rig, the mattress that comes with it will likely be terrible.
You need an electric foam cutter. These tools aren’t expensive and can cut through foam like butter. The final results are a smooth and clean cut without jagged edges.
If you don’t like the idea of making your own cut-corner RV mattress, some companies will do it for you. TOCHTA and Mattress Insider are two of the most popular choices for this.