Once you kill a fish from osmotic shock, you'll change your mind about plop and drop. This has been discussed over and over in the past. Do what you like, if it works, it works. But just because you've never killed a fish doesn't mean plop and drop works and is 100% safe, it just means you've been lucky. If you have a fish that's sensitive enough, then you suddenly drop them in water that is very different in terms of TDS and GH, you CAN kill them as their internal regulation can't cope with the rapid change in hardness levels.
I would NEVER even think about cutting the bag open and dropping in my wildcaught discus into a new tank without a long acclimation. When they arrive, I pour them all out in a 5g bucket, add Prime, aerate with an airstone, and drip acclimate for 30-45 minutes minimum.
I would NEVER even think about cutting the bag open and dropping in my wildcaught discus into a new tank without a long acclimation. When they arrive, I pour them all out in a 5g bucket, add Prime, aerate with an airstone, and drip acclimate for 30-45 minutes minimum.