If the 4.66 TH/s instead of 4.86 TH/s is true, and many of us begin to receive a similar email, what would be a reasonable discount?

Anyone care to chime in?

$1,823 + $47 shipping = $1,870  divided by 4,860 GH/s = $0.38477366255144 per GH/s. 

If it's missing 200 GH/s x $0.38477366255144 = $76.9547 ($77) discount?  What do you think?