Tser

You can also lock the object_merge so it's not connected to the original objects and delete the original objects so you only have the one object if you don't need the original objects any more.

I don't know if this is the same thing, but if you create a Geo object, dive in and add an object_merge, use it to add all the objects you want to modify all at once, select "Transform:Into This Object", now make the original objects invisible by turning off their display flags, now you can modify all the objects points/faces/edges into whatever shape you like, you can even transform the original hidden objects which translates to the Geo objects.

noicevstime
Hi! Any possibility to see a demo video to see how it is working?

Yep...