$400 is crazy for a 11 meter ground plane.
It does not matter how much $$$ is invested in equipment.
There are multi thousand dollar HF rigs talking off a wire every night of the week.
IF your QTH is high wind,,snow and ice location and there is a need for physical strength of an antenna to withstand the climate then yes a strong built antenna is needed.
Still $400 is a lot of money ,,you can go buy sch 40 alum conduit and build your own for a 1/4 of that price and it would be even stronger.
I have heard nothing but good reviews about this antenna,,then again anyone who spends this type of money would not say anything bad about it.