The middle quote is about right on with the insurance company. Their
shingle estimate is 58 sq vs 57.33 for the insurance company. They are
proposing the the 30# felt and use a higher nail count. When we bought
the house the previous owners had to replace shingles prior to the sale
so I am conscious of losing shingles in high wind.

Thanks to all for the help.
Eric in North TX wrote:
2) Is the felt difference important?

3) I have read of 4 and 6 nails recommended. I understand 6 would be
better. How much better?

2
There is nothing more important to a quality roofing job than 30 lb
felt, IMO.
I know many, many people will tell you it is only a moisture barrier,
but think about that, the roof is only a moisture barrier. 15 lb is
like black newspaper in more ways than one, it tears easily even when
new, disintegrates at a touch when a few years old. They will charge
considerably more to use 30 lb because it costs twice as much and
covers half as much, also it is harder to work with, but well worth the
effort it the "life of your roof". BTW, I'm residing a 50s house and
they used 30lb in some spots, 15lb in others for house wrap. When we
have to remove the old siding, the 30 is re-usable, the 15 usually
falls off and hasn't been doing the job for some time.
3
That really depends on the likelihood of high winds in your area. I
would always go for more nails, but 60 - 80 mph winds are very likely
in my area.