I stood in the marine store and looked at 75 feet of shelving lined with dozens of bottles of boat wax, reading descriptive words like premium, ultra, UV protection, nano technology, exceptional, durable and easy-on. In some products, the label carried three or four superlatives. The average price for a 16-ounce bottle was $22.96, not counting the $4 bottle of Turtle Wax we tested. The highest was more than $55. What a dilemma. You know it and I know it, but what we don’t know is what really matters when buying a wax for the boat. What works best?