Personally, I don't see the value in "Whiting True Blue". I have never had them, but I'm pretty sure my line of Cream Legbars would exceed them in every category, plus they are autosexing.
If you want high volumes of blue eggs, make a hybrid to benefit from the added vigor. I used to use California Grey pullets from Privett Hatchery, with a Black Ameraucana rooster to make black sexlinks that looked like Ameraucanas, were easily sexable at hatch, and laid so many blue eggs.
If you want a true breeding, homozygous for blue egg, breed, try Cream Legbars, but get an exceptional line of them from a responsible breeder, not from the hatcheries. When they were first introduced to the US, it really took the poultry world by storm. It is one of the few breeds that actually lives up to its hype. At the time I was raising standard bred Ameraucanas (still am) and I did not want to like Legbars, but after keeping them for a year or so, I realized they were simply the best possible breed for backyard chicken keepers.