As far as drop safe goes, there are two things you have to be concerned about:
Dropping front down, like you aimed for a holster and missed, this is what manufacturers classicly test for. This can cause a discharge if the gun hits hard enough for the striker pin to impact the primer with enough force to fire a round without the trigger action ever cycling. This is prevented by a striker block safety.
Dropping back down, like if you somehow fumbled the gun and it landed backwards, with the barrel pointed upwards, classically manufacturers did not test for this. This can cause a discharge if the trigger weight slamming backwards is enough to overcome the action and fire the gun. This is prevented by either a trigger blade safety, or a lightweight trigger, or a heavier action, or some combo of the last 2. The Sig p320 is a good example of this, the civilian version came with a heavy trigger and it wasnt drop safe, you put in a lighter trigger and suddenly it is.
All my triggers and the factory trigger with the blade safety mechanism removed are all pretty close to 0.1oz, and I have dropped my personal PT111G2, which has polished internals, backwards 20 times in a row from a height of 4 feet onto a thin vynal covered concrete floor with my SAO trigger and never had the trigger action discharge, so personally I wouldnt normally worry about drop safety with the safety blade removed from the stock trigger, or with any of my SAO triggers. However, if you have heavily modfied your trigger action to discharge much easier than it would from just polishing and breaking in, or if you are consistantly dropping your gun backwards from a height of over 4 feet, you may have an issue, as I have not tested those circumstances.
I cant think of anything that keeps the warranty in tact if you put in aftermarket parts, which is why I encourage people to keep their stock parts for anything. If I buy a new Dell laptop and switch out the mechanical hard drive for a much faster SSD, then the motherboard dies, or the screen stops working, you can bet I am going to put the stock hard drive back in before I ship it to Dell. Same story with the warranty on a Taurus, or any gun manufacturer.