I did not know that. I almost went went the Viper the first time around. It doesn't surprise me though, buying designs and processes is part of doing business. Apple bought NEXT just for their operating system(and got Job's back with it), and car stereo amp designs make the rounds also. Out of the hundreds of tire brands out there, there are also just a few manufacturers. Its the quality of parts used in manufacturing and assembly that make the difference. Whether they pay in house designers, or outside designers, it's still their product. I hope this doesn't sound like an argument, constant product updating is what I would call, trial and error. It's the law of averages. The more balls you throw at the hoop, the more balls will go in. I like mares for their simple design. I use them at 30' in Hawaii, 180' in the Caribbean, and everywhere in between when cave and cavern diving. They haven't had even the slightest glitch, but I am also obsessive about cleaning. Thanks again for the info, adown