Grumpy,
Thanks for your $.02!..
Yes, Out builder has been quite good to us (as good as the builder-buyer relationship goes). We actually did have the roof looked at by a highly trusted roofer of 20 years that did my in-laws roof recently and he didn't get up on the roof but he inspected the shingles as well and gave us the number for certainteed to at least go through the claim process.
I read there is some acceptable variance from the nail line, but after I flipped the shingle over, it's clear that it would be better to be below it to penetrate both layers vs above it and you miss the one layer all together... All of these missed both layers.
Builder states that I live on a very windy street, but the Landmark 25 shingles are rated at 70 mph and 80 if 6 nails are used... I'm far from a roofing expert, but did print out the installation instructions and have surfed the net to see what is correct.. Heck, I installed the roof on my 12 x 16 shed and not a single shingle has flown off .. And all of my 21 neighbors have no problems either. As for less than 3 nails or u evenly spaced nails, the builder told me once the shingles adhere to each other, that's not an issue (phooey I say!).
Thanks again for your opinion.
P.S. We do have one leak that we discovered as I got dripped on in bed, but it's where shingles are missing and the builder & roofer were supposed to come today to look at the roof and we've put a bucket in the attic to catch any water..
Take care,
John