This thread will cover the four Sailor Moon belt scrollers currently in existence, though I've only really put time into the first three at the moment.
Game Overviews [UNDER CONSTRUCTION]
Bishoujo Senshi Sailor Moon (Angel, August 1993)(SFC)
The first belt scroller starring everyone's favorite team of superpowered schoolgirls is a slow but serviceable Final Fight clone. You have your standard Jump and Attack buttons that perform a desperation attack when pressed together. With the exception of Minako, who uses her Love-Me Chain like a Belmont's Vampire Killer, all characters can perform a standard 2-5-hit combo that can be topped off with a throw by holding down on the last hit. Each character can also unleash a projectile attack by holding Attack until a bar fills up, but the process of charging the attack is too long and the resulting damage output too little to actually be useful.
Once again, this is a very slow game. Only in Stage 2 does it actually begin to pick up. Aside from Red Battler's unbelievably bullshit hitboxes, its mechanics aren't too shabby.
Bishoujo Senshi Sailor Moon R (Bandai, December 1993)(SFC)
Bandai actually surprised me by putting out a fairly solid sequel that improves upon the Angel game in every conceivable aspect. In addition to all the mechanics that were present in the first game, R bestows upon each character a powerful piledriver-like move performed by jumping and pressing A while grabbing an enemy. This is an invaluable tool for crowd control, and knowing when to use it can mean the difference between a full bar of health and an empty one. There is also a screen-clearing super available to each character that can only be performed twice per stage. Collecting a ribbon icon will allow you to perform the attack a third time, but these are exceedingly rare and I can count on one hand the number of times I've found more than the guaranteed one in Stage 2.
Which brings me to score, extends, and item drops. Even though there is no visible score counter, the game does keep track of score in some way and grades your performance at the end of each stage based on time of completion, health lost, and score items collected. Efficient play without dying or losing too much health will almost always yield an extend early into Stage 1 and two in the first half of Stage 2, assuming you collect all the items up to that point. Further skilled play can net you at least one additional extend in the second half of Stage 3, though I've never made it that far without dying at least once. The most lives I've managed to accrue are 7, but I suspect 8 is possible if you don't get hit as much as I do. There are actually a handful of breakable objects whose contents appear to change based on how much damage you take, but I have not yet been able to manipulate the contents of said breakable objects consistently. I do know it's possible to receive ribbon icons from them as well.
Bishoujo Senshi Sailor Moon (Arc System Works and TNS, August 1994)(MD)
Famously developed by Arc System Works. It's... all right. It appears to be related to the Super Famicom game in some way, featuring many of the same stages and enemies. While it has marginally better presentation, it's rather janky in comparison, as enemies frequently outrange you but are also ridiculously easy to stunlock indefinitely.
Bishoujo Senshi Sailor Moon (Gazelle, March 1995)(AC)
The Gazelle game sports marvelous production values and was supposedly overseen by Takeuchi herself, so it's definitely a game I'd like to look into at some point... assuming I'll ever get over the Stage 1 bosses basically being able to break out of your combos whenever they want.
So I finally got the 1CC with Ami today, and even had two lives left in stock. Despite having little range and dealing less damage than just about anyone else, Ami has great mobility and her grab -> Y attack has fairly quick recovery, making her a decent if tricky choice for a clear attempt. Her long throw also lets her have a better time with the raft sequence than you would think. As I've stated in the main thread, her Jump + Attack special also leaves a bit to be desired since it takes a while to come out and can't hit enemies low to the ground, but it still has good horizontal range and doesn't take off too much health.
Spoiler
Ami, giddy as a schoolboy after single-handedly saving Crystal Tokyo.
Rei's special attack drains entirely too much health. It's no wonder I was dying so much with her. Just compare these screenshots:
Spoiler
Minako's special drains the least amount of health. Ami's and Makoto's drain a little more than hers, while Usagi's depletes more than all three of theirs. Rei's is dead last.
Spoiler
And this is just for one attack. Considering how much damage green Dumbles or yellow Jaamanen can do with a single grab...
I also decided to try putting a little bit more time into MD Moon after discovering it had infinites. As it turns out, it's actually possible for Usagi, Ami, and Rei to combo into their special moves, and said moves actually provide some generous i-frames. Rei's Screw Upper* in particular is a good way to stuff jump attacks from the deadly clown bots. I suspect the game would be much easier if anyone could figure out how to get them out consistently - so far I've only been able to pin down Usagi's and Ami's, which are DUDU + Attack and DFDF + Attack respectively.
*as I have dubbed it, after the SNK super it resembles.