I use the actual areas in the game to test damage now, instead of trying to do guess work with the dummys and looking at d2/ingame stats, it works out
that way because of the complex interplay between all the different factors, and ultimately what your real goal is, is to perform well in the various areas of the game, and in boss fights.
So in the early game hell diablo is a good boss fight to test damage on, which is evident by the time it takes to get him down, which should even have visible differentiation you can deduce on your own. Then there are farming areas of the game, but what you have to keep in mind is that the different areas have different kinds of monsters, with different kinds of resistances, so different weapons, different builds, different stats will all perform uniquely, and uniquely in all of the different areas. It should be very obvious how well different configurations for your character, whether or not it's gear, or your build will perform, if you just pick a couple areas to test in. Pick a couple different bosses, pick a couple different farming areas, and give it a run. That's how I do all my testing now...
You will see the most dramatic differences when there are more people in the game too, p8 games will actually allow you to see very easily how strong your character, and different builds/gear for your character, really is unlike any lesser difficulty mode.
Also the rule of thumb I offer to new players is to keep all the stuffs they find useful, because of all the unique areas, different items will allow them to complete all the various unique challenges, where unique gear, unique stats, will benefit them, and give them the edge they need to keep progressing in the game.
