Relatively short life - seam failed

I have owned a waterbed since 1977. This is the third mattress I have purchased meaning that the overall average mattress life has been about 12 years. The prior mattress that I purchased was a Naturalizer 100 in August 1988 for $69.95. That lasted until I wanted a firmer mattress in 2004 (16 years). At that time, I thought that I would purchase a top of the line mattress this time around - if a lower end mattress got about 14 years on average, I should expect a top of the line to get even better life. I was wrong. The Land and Sky 8500 ($649.95 discounted online to $359.95) lasted about half the life of the prior mattress - only 8 years, though it cost me five times the price. It failed at the seam of the air-jet release valve where it attached to the mattress. And that second valve was a selling point. Wrong - more seams means more places to fail. I would not by this again - I never used the second air-jet valve anyway. I burped the air the old fashioned way back out the water inlet. If the air-jet valve was not included I would still be using the mattress.