I'm playing through this, and enjoying it for the most part.
I've only played Musou and the versus games, but it feels like to me that they pulled out elements of each with this.
Pros - I like the customization, and that you really have to think about your style and what load out you want to take, while also taking command of your squadmates. I like the graphics overall, and to me I feel like I'm in the middle of the action, once you get out of the deserty stages, I really liked the Englad base stage, and the forest stage in Indonasia (I'm about 6 or 7 missions in), and I like the quality of the details on the mobile suits. Sound effects are good too. The animation is more comic book panels than actual animation, which is eh, but I like the presentation and the other cg effects.
Cons - If you come in expecting arcadey action like the versus/musou series than you're going to get your ass handed too you it seems. There's much more emphasis on strategy and what your loadout is, along with your squadmates. I've never been much for micromanagement, so I tend to pimp out my mobile suit and leave the rest to their own. This has started to lead to my teammates getting knocked out of the action faster which means less support. Can't go in on basic loadouts, basically. Other than that loading tends to be a bit longer than expected, and that with installing to the HD.
I've only done a few co-op missions online, JP players seem to be all about playing on Hell setting to get points. Need to try the battle royale mode as that looks to be the watered down version of a Vs. game mixed with Senjo no Kizuna elements.
Oh, jgaffer and can only play late nights or weekends, but hit me up if you want, psn is cloudv.