Posted some of my thoughts in the meta discussion thread but I'll post some more of them here since I've played around with some other teams featuring or beating these since then:



Mega Latios:



This functions very differently from regular Latios and should be immediately compared to Mega Latias (minus some bulk but with a better offensive presence to make up for it) instead. This alone makes it extremely questionable by UU standards, and that doesn't even factor in its ability to run effective mixed sets should it need to. This thing has a lot of versatility and it's on something that already has a tremendous amount of versatility and I firmly believe this thing should be quickbanned ASAP as it has no place in UU.



Latios:



I don't think I want to see this quickbanned, but it doesn't take more than a single game to realize why this thing is a top-tier threat that absolutely warrants a public suspect test: everything Latias does offensively is done even better by Latios, and that's terrifying. Latios scores OHKOs and 2HKOs (frequently with only a little chip) that Latias can only dream of, such as a 55% chance to 2HKO Blissey with Life Orb Psyshock after Stealth Rock, the ability to easily 2HKO Alolan Muk on the switch with +1 Gigavolt Havoc into Draco Meteor, the ability to always OHKO Mega Aggron at +2 after Stealth Rock and to frequently OHKO it after only a little (about 20%) chip, etc. While Healing Wish is great, Memento is also great as it gives Latios yet another option on Hyper Offense teams. In addition, it and Latias have near-perfect synergy with Bisharp, which is another new addition that is very welcome here. It's definitely extremely powerful but I think we should give it a chance.



And yes, in my opinion CM Electrium Z is better than Specs. Specs isn't bad, but Electrium shreds everything.



Bisharp:



I've seen a lot of people here say it's unhealthy, but I quite frankly don't see it. The tier has no shortage of checks to Bisharp on both the offensive and defensive ends of the spectrum, although Bisharp does have the movepool to work around this as one sees fit. It's an extremely welcome addition to the typical Spikestack core of Mega Sharpedo+Klefki+Mamoswine, but it also doubles down on several weaknesses in providing that anti-Defog utility. It seems incredibly good, but not as blatantly broken as Mega Latios and not as terrifying of an upgrade over a top-tier threat as Latios. Cobalion, Infernape, Lucario, and Terrakion are all pretty prominent right now and they can all deal with it handily; alternatively, bulkier teams can still pressure it with Unaware Quagsire, Mega Steelix, Defog Moltres, etc.



Make no mistake: Bisharp is gonna have considerable influence over the tier. But it's most certainly not unhealthy. It should absolutely remain here since it's a very welcome addition to offensively-oriented teams that adds something new to them instead of cranking up a staple's power even further.



Zeraora:



Great speed tier and an incredible movepool are two great things Zeraora has going for it. It can pick and choose what counters it and it has a pretty good niche as a stallbreaker since it hits almost everything on those archetypes for brutal damage, or can alternatively treat some Stall staples as setup fodder for a Bulk Up or Work Up variant. It's the "worst" of the four drops, in my opinion, but I still firmly believe it'll have an impact as a solid A or A+ threat.



EDIT: Zeraora's pretty nuts. I hate playing around this thing since Bulk Up is a horrifically powerful wincon against Stall unless you're running Quag or Mega Aggron and even without Bulk Up this thing still hits like an absolute nuke and Quagsire still folds to Grass Knot with no trouble whatsoever. May wanna consider suspecting this although I really do want to give it a chance.