haha thanks for the karma gymtime.
with my vague assesment i was stating the fact that they are good, but should be used only sometimes, and should be used to mix things up.
there are many things you can do(other tools in the toolbox), short rest times, 21s, long eccentrics, etc etc, like all these things, drop sets have a special place for a shock to the system.
I some times prescribe them as a body part finisher with someone who has a bit of experience behind them....but only on a day where they dont seem challenged