Detailed and informative guide by Dethklok that gets into math to help determine what Monster Power level you *should* be playing on for the most efficient/profitable playing experience. Now that the MP system is in, I’ve seen a lot of players talking about playing on the highest level possible, for the experience and Magic Find bonuses. And that’s one approach, and if that’s what you enjoy go for it, but it’s not actually the most efficient way to play, in terms of how many high level rare/legendary items you find per minute. Which is where Dethklok’s math comes in.
You need to look over the whole thread to get all the context and nuance, but here’s a key quote:
His math then proceeds to figure how much of your total time is spent DPSing, vs. other stuff. And that’s where it might confound your expectations, since the slight bonus to Magic Find and experience that you get on Monster Power 2 or 3 is almost certainly *not* worth the added time it takes to kill those enemies. Even for very powerful characters.
Farming consists of two essential types of events. One of these is DPSing, the act of actually attacking monsters to make them drop loot. The other, far broader category, we’ll label downtime, a blanket term to cover anything that isn’t DPSing. Running from a dead monster pack to a living one, kiting (maneuvering around living monsters for survivability purposes), deaths, recharging (waiting for cooldowns to reset or resources to regenerate), selling items to merchants, stash dumps, and even putting found items up for auction are all considered downtime. However, only serious time counts; inefficiency caused by not really playing the game with your full attention does not count towards this definition of downtime.
Unfortunately, the line between downtime and DPSing isn’t quite that clear-cut. Killing white mobs doesn’t have the same magic find potential as killing elites, and the time spent DPSing before achieving 5-stack valor is not as farming-effective as time spent on 5-stack. For the moment, we will assume that such activities count as partial downtime; finding the exact coefficient would be a subject for later inquiry.
A quick glance at the MP chart shows the monster health outpaces increased magic find, even at MP1. Therefore, only downtime can make a higher MP level more attractive. However, as DPS increases, DPSing time naturally goes down, increasing the relative amount of downtime in a given farming run.
The big exception is key farming, since on that higher levels of MP makes a huge difference in how often you’ll get a key or a demonic organ.
If you have a very powerful character capable of easily handling the higher MP levels, this is an area where you actually enjoy a competitive advantage over other farmers… as opposed to, say, trying to out-farm Legendaries against a Tactical Advantage spamming demon hunter with low defenses who runs MP1 Act1 over and over again. Very many characters can farm items efficiently; very few can farm keys well. As such, high-powered characters who aren’t keyfarming are pretty much doing it wrong.
The final prescription for most characters:
The possible exception is if you’re one of those people who obsesses over “almost” item finds, in which case you might want to push up your MP to the highest you can manage all the time, just so you won’t feel like you just missed out on an awesome item.
That used to be fun to worry about in Diablo II, since the item quality went unique > set > rare > magical. So if you found a set or rare item of the same type as a unique that you really wanted, you could curse the RNG gods and gnash your teeth and wish you had just a little bit more Magic Find, since that might have made the difference and you’d have rolled the unique instead.
That same logic works in D3, but not as obviously, since you find such a huge number of rares (and tiny sliver of legendaries) of all the highest item types on Inferno that they sort of blur together. My DH is desperate for a bow upgrade, but I find rare Revenent Bows so often that I no longer get my hopes up, and I certainly never think, “Wow, that was almost a Windforce (db)!” (See, we do notice item types in Diablo III… sort of.)