Unfortunately, my experience has been that this sort of thing is VERY common. In generally, the longer the warranty, the more likely it it to be bogus.
I should note that, at least in my area, AG pools are considered a service market only for losers (as in, pool guy losers). 'Successful' AG pool guys are builders with an 'in, out, paid, and gone forever' approach. I don't know about other areas of the country, since I don't have many pool guys on this forum, and anyhow, it's not something that they would discuss in front of customers.
But the brutal truth is -- it's HARD to make money doing AG pool service. I won't get into the reasons, but they are quite real.
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