Need to buy a new trigger today.

[Fodderwing]

is there any trade-off of going to a drop-in trigger, vs the more conventional 2-part units? Is it just cost, or is there a weight component to that as well? Reliability/blown primer tolerance issues?

Drop in triggers work great in most applications. But don't put one in a 7.62x39 upper and try to shoot Russian ammo, the hammer springs will not set off the primers. I learned the hard way.

I switchd to a high polish nickel boron trigger with an enhanced hammer spring in the lower dedicated to my 7.62x39 upper. The kit shipped with 2 springs, standard and enhanced, color coded to distinguish the two.

Now, if you roll your own or buy brass ammo only, you may never suffer light strikes in a 7.62x39.