I would not invest in this venture. That is not to say it is not worth pursuing – only that, as an investor, I am unlikely to see a large ROI. If you make a product that is the best on the market and promote your company well, you could be very successful, but the venture lacks a disruptive technology or idea that would give you an unfair advantage. Since the only thing differentiating your company from others in the ELL space is making a high quality product, I fear your competition will be stiff. Best of luck!