And these Japanese episode titles crack me up sometimes, they're so literal.
Four Warriors Come out of the Sky
The first thing that strikes me about this episode is that the animation is a huge step up from season 3 of the US show. It's not bad at all for tv animation. The characters are generally on-model, and move fairly well. There's a ton of action, almost non-stop. And the second thing I really enjoy is seeing so many of the season 1 and 2 character interacting with the later characters, something we rarely saw on the US show. Prowl, Smokescreen and Jazz all show up, along with Sideswipe and Hound.
So Galvatron's after Vector Sigma, and he sends out his new Headmaster troops. An all-out battle is waged on Cybertron, so they call to Earth for help. Wheelie and Daniel beat Trypticon (really, no kidding), and the Autobots are losing when (as the title indicates) four warriors come to Cybertron and turn the tide of the battle.
If you squint (metaphorically) this show could easily fit into continuity with the American series. There are one or two things that don't quite fit (such as Prowl's survival), but otherwise it all feels very familiar. It's nice to finally get to watch it.
The Mystery of Planet Master
One thing I"ve already noticed after only two episodes: the storytelling is different. The show seems much more serialized than the US show, as this episode picks up right where the last one left off, and there's no self-contained plot for the episode. It just adds a new plot thread or two, and advances other plot threads. The Matrix is still empty from being used at the end of ROOP, and Hot Rod goes to Earth to find it. And since when did Soundwave and Blaster get such personal animosity towards each other? That came out of nowhere. They kill each other in a fight, though since I know about the Soundblaster toy repaint, I'm reasonably certain they'll both turn back up at some point.

It's nice to watch this show and see so many familiar characters. One thing the translators got right with the subtitles was using the American names for the characters. So Optimus Prime doesn't end up as "Convoy" for example, even if that's what the character on the screen is saying.
I can't quite decide about the serialized storytelling, where each episode is pretty much just a chapter in the larger story. It certainly keeps me wanting to come back and see what happens next, since there's very little closure, but it's hard to review individual episodes since there's no self-contained story. I like what I"ve seen so far though.