Trigger and safety appear to be the same as the 92FS...which was my first firearms purchase in 1994 and still going strong.Sounds like firing them from the Beretta is the way to go on the first pass. Beretta may have based their firing pin energy on the military spec they use in the 92s. I don't know, but more energy is more energy and seems to be what your primers are getting from it and need.
The light bullet will offer a lot less inertial resistance for the powder to build pressure against, so the light load behavior is not unexpected. But you are right to be cautious with the deep-seating bullets and work up slowly.
I'm not quite convinced that these primers are good to go in the PX4. I'll be delighted if they are, but more testing is necessary. Running 16 rounds through without a failure is still within the range of expected outcomes for a 10% failure rate. Once I've run at least 100 rounds through successively I'll consider them good to go for more than plinking...in the PX4.
Regardless, I still got free primers with my less than 1/2 price new brass. That's the bonus. I only found this deal because I'd failed to obtain once fired brass from any source. With 2000 cases, I'll be generating my own hoard of once-fired 40 S&W.