I picked up a max weigh MJ Z Comet from a local vendor while weighting for a ~175g one from Infinite to arrive. I chose this disc as an understable, shapeable companion to my Buzzz, and especially to fill the gap for low straight shots at 225-250' that are touchy for putters (where I find I need more height) or where other fairly neutral mids will tend to fade left. I also wanted to start developing an anhyzer/turnover game, which I'd been neglecting while learning other things. Lots of searching recommendations online landed me back to the Comet almost every time.
The Comet is unlike any other disc I've thrown. It's got a bit of a bead and is wide and domey. Its balance feels a little different. So, it's understandable that those features might cause some players to hesitate or dislike it based on the feel alone. However, I'll make the positive case that you should get one and stick with it.
First, as a player with ~9 months of experience but an obsession with improving form and consistency, throwing the Comet almost automatically started improving my touch and control. I first threw it in an upshot fieldwork session. This disc seriously punishes poor grip and timing, bad angles, and off axis torque. It equally rewards clean releases. At max weight, it can take a lot of clean power with no problem, but a little wobble sends it turning fast. Compared to any other disc I tend to use in the 200-300' range (e.g., Pures, Proxys, Envys, Mako3, Buzzz, Emac Truth), it seems somehow to make me more aware of my release point & the last pressure point on the disc. But I have to say, as soon as I figured out how to throw it flat 200', my technique with other discs was immediately more sensitive and controlled. It might take more or less time to get the feel for the Comet depending on your prior technique, but IMO it's worth it, and I wish I had used it to learn to throw low, flat, and straight earlier. I almost wish I could rate it "friendly for beginners who wants to be maximally punished and rewarded for their form".
The disc itself is a marvel. The gliiiiiiiide is real. The comet just likes to hang in the air, fading mostly forward unless you shoot it nose up, high, or give it too much OAT. A little too much power sends it sailing, so watch out. On good throws, it was the best feeling midrange disc I've thrown due to its responsiveness. It holds a hyzer and anhyzer line just fine. My brand new max weight Z takes a hyzer flip at maybe 250'+ power, but holds the hyzer or a nice flat shot with minimal turn at less power. It is not a "turn and burn" disc at all (at least in max weight) if the releases are clean. It's nice for soft, glidey turnovers that won't skip.
The Comet fills a role that isn't quite covered by the Buzzz and Emac Truth since those discs are a bit faster and more stable. At my current skill level, I can more confidently crank on a Buzzz or Emac farther out with less worry that it'll turn due to OAT on a bad release. But if I need a midrange touch shot, Comet all the way. Relative to the Mako3, the Comet is slower, a bit better suited to shorter range neutral shots, and more understable. So it's got a fairly special and unique role, but mileage may vary depending on the player.
Even if you think you have the shots that make the Comet redundant, I minimally recommend it for a practice disc to improve form and touch.