I think if you removed all the posts on the MC3000 on the Internet, there wouldn’t be much left to read.
All battery chargers have the same goal, to charge your batteries, and there are only two requirements to make a great charger. 1) The charge current, voltage and battery temp. can’t be too high to damage the cell, and 2) the charging process can’t stop until the battery is correctly charged, not over charged or under charged. That is it. Period.
So if a charger can do #1 and #2 well, that is all is needed. Problem is, its hard or impossible to do both well for many types of batteries without some human input.
I have the Opus v2.2, and its a fine charger, with human input required for accurate charging rate (#1). It performs (#2) O.K. but it undercharges in most cases, but it trickle charges after to compensate.
Batteries, even of the same chemistry are different and some tweaking of settings can almost always help.
The MC3000 is nothing more than a charger where all the charging parameters can be adjusted, so if they are set correctly for a particular battery, the charger works well. But two negatives. 1) You must learn about all these parameters to set them correctly. AND 2) and the MC3000 has a pretty bad user interface. It can store many charging profiles, so if you take the time to set these, its relatively easy to use after setting up. Many people may not want to bother, when the Opus can do the same but maybe only charge to 80% full when it stops. And the charger is cheaper.
So if you are a person that wants good precision and your willing to put the time in, the MC3000 is great charger in the right hands. If you just want a throw batteries in charger that will mostly charge OK, you probably don’t want the MC3000, and it will be frustrating. For this I like the Ansmann chargers, but batteries can run a bit hot. Most batteries are tolerant of this, however.
Oh, I should also say the Bluetooth on the MC3000 sucks, and bad instructions make it worse. In my opinion, unless you can get the smartphone interface running, than I wouldn’t bother with the MC3000 because the basic UI is BAD, as mentioned above. Use the phone interface if you absolutely can.
So do you want to spend almost no effort to get 80% charged batteries? Or do you want to spend a few hours learning and programming to get your batteries at 100% charged? Your choice.