I just placed my 3rd order with Layne. Price and quality of the mice are great, but yes with shipping it is only economical with 2 or more snakes to feed. I order for six months at a time. My price, including shipping works out to $1.03 a mouse. That's enough less than PetSmart to make it worth the effort.
As to the complaint post, which looks like a google and sign up just to complain, Layne quotes shipping before you buy so anyone can take or leave it. They clearly state they only ship 3 days a week and so if you order on a Thursday it can easily take 6 days from order to delivery. This is clearly stated on their web site. If you don't like that, don't order from them.
My mice have arrived well packed, hard frozen and are top notch. The shipping price is not the lowest but the quality is high and because they will sell in bags of 10 and 25 it can work out for us small time keepers with snakes at differing prey size needs. I looked at other deals this time around but went back to Layne.