The explanation provided by Dr. Czilia Avoqee successfully won her audience after she initially scared them away from purchasing her product.
The stealth field fey may be fragile, finicky, energy hungry and prone to failure in many conditions, but so what?
As long as a mech force properly accounted for all of these weaknesses and took measures to minimize exposure to them, the stealth field fey could still be utilized to secretly sneak over a bunch of mechs and other stuff!
Technology was all about recognizing limitations and working around them. Ves shouldn't be so surprised at this because third-raters and second-raters often had to work around them in their daily lives.
Even first-raters weren't exempt from the boundaries imposed by their physical reality.
They just had it a lot better because they could spend astronomical sums of money to obtain extremely inefficient but somehow effective enough solutions for most of their problems!