See also this thread:
The GP100 is in some ways the smallest 357 that can cope with unlimited diets of the harshest stuff possible.
The only way you can hose one is "Bogarting" the cylinder (snapping it closed with a twist of the wrist) or handloading past the old-school spec of 43.5k PSI pressure. (The new SAAMI spec of 35k) was dropped due to the proliferation of "micro-357s".)
Yet the GP can also do rapid-fire of light loads, which is also harmful to lesser guns.
Dry-fire it a bunch to smooth up the trigger, maybe do a spring job, do grips to your preference, maybe sights. If it has any flaw it's that the rear sight bodies can wiggle slightly in the frame in some specimens...a Bowen rear sight will fix that if it's an issue.