Not as good as I was expecting.
As you start the game, you can choose between two characters, Vent and Aile, who are both new to the Mega Man series. You start out with your normal buster, then as you go through the game you get sabers and more powerful busters. You can also go in your human form, which may look useless at first, since you can't shoot or anything, but you can do something you can't do in your other forms: ducking. This useful for when you need to fit through a small spot. I was a bit disappointed to see no Zero or any character from other Mega Man games, but being able to use a saber like Zero's sort of makes up for that.
Unlike the Mega Man or Mega Man X games, you don't just choose what level you go to. The whole game is basically just one level, much like the Metroid series. You can, however, choose which mission to do, which can vary from saving someone to defeating a bad guy. One cool thing is that some areas in the game are pretty familiar, for example, there's this one area in the game which is almost an exact replica of the introduction level in Mega Man X1.
This is a fun game while it lasts, but it's not nearly as fun as just about any Mega Man X game. I was also disappointed in how easy the bosses were. They are all weak to the standard saber. Just jump and do the saber spin a few times and they are done for. At least the bosses weren't all weak to the same weapon in the other games. Most of them were weak to a different weapon. The reason I listed the difficulty as "Just Right" is because sometimes, it can be easy to get lost.
Overall, this is a good game, but not good enough. I hope there will be some improvements in the sequel, Mega Man ZX: Advent. My real rating for this game would be 7.2, but due to the new review system, I rounded it to a 7.0.