I recently purchased add sadly returned your self emptying model. My problem is a 2950 sf floor plan that the machine could not map. The concept of your machine is excellent. One of the few self emptying models on the market. Its just a dirty shame that the computer that operates this machine is dumber than a shovel. I would buy this machine again should you improve the machines computer. Again, this is one of the very few products I regret having to return. C Battelle User's recommendation: If you have a complicated or large square footage this is not the model for you.