^^^ Maybe starting with five makes sense then. Under my plan, I think that two batches of five makes sense. In fact, the more I think about it, the more brillianter my plan is. You order four more to complete the five for Batch 1. After wearing these for a year or so, you can decide whether this is a good idea or not. When you decide that it is a good idea (because we all know you will), then you put in the order for five more for Batch 2. My plan keeps you from ordering two extra shoes right now, which is helpful in case the plan doesn't work out. However, it also allows for the opportunity to extend the life of all the shoes by doubling the amount to ten should you like the plan. Ten actually makes the most sense, even more so than five or seven, should you actually decide to keep these for 50 years.