The Sunsoft Collection is a small one, containing ports of just just two NeoGeo 2D fighting games: "Galaxy Fight" and "Waku Waku 7." As is usual in the NGOC series, they've added sprite color editing, an arranged soundtrack option, button mapping, and training modes. The emulated games run with a smoothing filter over them that you can't turn off.
Galaxy Fight is a pretty bad fighting game by any measure. The sci-fi setting is nifty, but the stage designs range from mediocre to hideous. Most of the character designs are kind of neat, but the characters don't animate all that well, many of the special moves feel a little off-target, and an overall sluggish framerate makes trying to do moves--or anything, for that matter--far more frustrating than it should be. The three attack buttons all do pretty much the same thing, the number of special moves is relatively limited, and there are no super moves, which leaves the game feeling pretty bare-bones.
A major difference between Galaxy Fight and most any other fighting game is that the stages scroll side to side endlessly in both directions. You can dash forward far faster than you can dash backwards, so it isn't really possible to keep running away forever, but I've played a few 2P matches where constant retreating was a pain. It's a useful tactic here due to the infinite retreat area, the very slow pace of the combat moves, and the short round time limit; if you can get ahead, chances are good you can just retreat a bit and time will run out, leaving you the victor.
On the default difficulty level, the AI starts out quite difficult. It ramps up a bit as you go along, I think, but the main difference is who you fight: the AI is far more effective with some of the characters than others. This makes single player a very uneven experience, even aside from the other issues.
Waku Waku 7 is a vast improvement over Galaxy Fight. The game has a very colorful, playful look and feel that just make it a joy to play. The cartoon-like character designs are some of the best ever to grace a fighting game, even though there are only seven playable characters. Most of the stages are amazing examples of colorful graphic design, and they have multiple times of day, changing as you fight through the rounds of a match. Even the game's menus are permeated by a hyper-colorful, bouncy exuberance that just screams "FUN."
The game is less perfect on a technical level, unfortunately. Although nowhere near as bad as Galaxy Fight, slowdown does crop up with relative frequency, particularly when fighters are using special or super moves; it's bad enough that it can make it difficult to get special movement inputs to register, which can make the gameplay frustrating.
The largest problem, though, is that they went a bit overboard with the super meter. I'm not sure how many charges it can hold, but I've seen at least five or six in there, and if you set it to auto-charge, it'll pump up a new charge every oh maybe seven seconds or so; the announcer saying "Charge" is a nearly constant sound.
You can do lots of things with a super meter charge. If you press a combination of buttons (the game uses the usual SNK NeoGeo four-button style: weak punch, weak kick, strong punch, strong kick), you can activate a time-limited SUPER mode where you glow yellow, and I think do more damage; when activating, this also causes an explosive burst around you that can floor your opponent. SUPER mode's pretty cool, and I don't have a problem with it, aside from the slowdown it seems to cause.
You can also use a super meter charge to super-charge a single special move attack by pressing both attack buttons (both punches or both kicks, depending on the move) instead of just one, similar to doing an EX move in Street Fighter III (see entry 439) or IV. The moves play with much bigger FX, and, coupled with SUPER mode, look pretty impressive (and cause even more slowdown).
Other uses of the super meter are a little more problematic. Most characters have a few super moves, and these usually take the form of a qcf-hcb (or qcb-hcf) stick movement, plus hitting either both punch or both kick buttons; doesn't sound too bad as far as complexity of super moves goes, but in practice, particularly with slowdown, it's very hard to get the input for these moves to register consistently, and the success rate, at least for me, was so low that I ended up relying on SUPER mode and "EX" attacks instead. (Ohh it would've been nice to have an option to turn off the emulated slowdown!)
The largest problem caused by the very active super meter are another form of super move that each character has: their "HaraHara" move. This uses just one super meter charge, and is easier to activate than the other supers, being just dx2 and either both punches or both kicks. When activated, the entire background changes to announce that the move is coming, and your character goes into a charging phase that lasts three or four seconds, during which they can't move. If they're hit during that time, the HaraHara is cancelled, and the super charge lost.
It sounds like a prohibitive requirement, but it actually isn't, because the screen zooms out to let you get quite a ways away from your opponent, and because you can start the HaraHara charging while your opponent is knocked down; I've seen the AI fire off three HaraHara's in a row at me--not that I was doing the best to avoid them, evidently, but still... HaraHara's can't be blocked, and are so massive or so long-range that they're usually pretty hard to dodge. If they do connect, they can potentially remove well over half of your health meter.
This seems significantly overpowered to me, and means that if you want to win, you're going to focus not on melee fighting, but on knocking your opponent over from far enough away that you can blast off a HaraHara before they can get back up and get to you. Doing that instead of fighting isn't all that fun. Some characters are much better than others at preventing HaraHaras--those with screen-spanning fireball moves, for instance--but they are such a game-changing device, and so easy to execute, that there's no way they won't skew the game away from actual fighting, which sucks. I still love the look and style of the game, and I can have fun against the AI--at least when it isn't abusing its HaraHaras (and this is more of a problem against certain AI-controlled characters than others)--but there's no denying that the battle system, which is otherwise pretty dandy, has one very lopsided aspect.
These ROMs have no English option, so all the win quotes and things like that are in Japanese.
Like other games in the NeoGeo Online Collection series, this one appears to support online matchmaking through the KDDI service, which I think in these cases is a Japan-only dialup thing, or something like that.