To say that I'm disappointed with this release is an understatement.
I'll skip the detailed griping about the pricetag, because others have already said and and I fully agree with them; this is absolutely not worth $10 per ROM when I imagine we've all had these games at our disposal on emulator for years.
The main question would of course be, "Well, what are the features you get that AREN'T just the base games I could have played on an emulator for the thousandth time?" Good question! The art stuff is undeniably nice, but the actual gameplay attraction on offer here is the Boss Rush modes.
This is the *primary* reason I bought this collection since, again, who cares about just owning the games when they've been easily accessible online for like 20 years. However, a structured Boss Rush mode, with a proper Time Attack system that records your best time? That's right up my street. I speedrun all of the the games in this collection, and Boss fights in the games I run are one of my favourite areas to optimise, particularly finding ways to exploit boss AI in order to get consistent results for fights that are typically seen as frustrating, such as the mech duel VS Axel in Sparkster SNES.
Regrettably, the Boss Rush mode in this collection is terrible. It's obvious that no quality control whatsoever went into this. Right upon entering the first boss of Rocket Knight Adventures, you're immediately presented with two issues: Firstly, you start each boss fight by pressing A which is also your jump button, and pressing it for more than a couple of frames causes you to jump upon loading into the boss fights, which is not favourable for some of them. Lovely. Secondly, the reason you can even *get* an instant jump on loading into a boss fight is because they decided to take the laziest path-of-least-resistance approach possible and have each "boss stage" simply load you into a static savestate.
This may not sound like a bad thing, but it has serious implications for Boss Rush, specifically. Notably in Sparkster SNES, many of the bosses are RNG-heavy. Randomness is a big part of the boss fights, and knowing how to react to what is currently happening or anticipate what may happen next is part of the game. However, the savestates for the boss fights are an arbitrary mish-mash of starting either before, or after the boss sequence has been triggered. What this means is that for some fights, you have control over setting the fight's initial RNG seed by walking into the boss trigger yourself, and for others you are locked into an RNG seed that you have no control over, because the sequence has already begun. Some of these RNG seeds are also DREADFUL for time-attacking, such as the Sand Worm in Sparkster SNES, which seems basically predetermined on the fight's set seed to dig underground. This is not consistent behaviour in regular play, but it is when the RNG is rigged, and it's against your favour for actually going fast.
This isn't even to mention that whatever emulator this release actually uses performs terribly. I opened with "People have been playing these games on emulator for 20 years" partly because that's literally what you're doing when playing this release, only it's an emulator with sub-standard performance in which frame skip will occur erratically without any apparent reason, and you paid $30 like a mug to play 30-year old games that perform better on unofficial software. Audio emulation is also very noticeably wrong for a few SFX.
I seriously resent how uniformly sloppy modern "remasters" of classic titles end up being. How can it possibly be hard to just re-release a title where all of the development work has already been done. I can only conclude that the development of these releases is handled by people who don't actually PLAY videogames, because nobody who was involved with playtesting these features and has a critical eye for detail can possibly have been happy with the final product. Sloppy, no attention to detail, no respect for the consumer.
Avoid, and play the original ROMs if at all possible instead.