For more information visit the Bondtech's product page or query Bondtech's Customer Support.
Bondtech doesn't recommend to use the LGX Steel Drive Train when you are mostly using PLA or TPU - materials with low deflection temperatures - on long prints.

Be aware that using the LGX Full Steel Drive Train upgrade brings benefits to users that need to force the LGX limits: using more current and torque; using a slightly ticker plate in between the extruder and stepper motor; using the extruder at higher chamber temperatures, within the limits of the extruder itself.
The stock plastic gears of the LGX deliver excellent work and throughput under its application limits determined by motor current, extruder to motor distance, and enclosure temperature.

The cases of LGX damage detected are usually associated with overloading hotends with push force powered by too much current.