Personally, I find it, easily, the best shmup available on Steam.
If you enjoy shmups of the "classic" variety (not bullet hell), you'll probably love this.
The game has a ridiculous amount of content to keep you busy.
Basically, this release includes:
-an arcade perfect port of DARIUSBURST: Another Chronicle EX, playable by up to 4 players in it's original 32:9 aspect ratio, which includes the Original Mode (featuring the stages from the original DARIUSBURST: Another Chronicle arcade), the Original EX Mode (featuring 12 new stages from the EX version of the arcade), as well as the Chronicle Mode, featuring 3000+ stages and variations, which you work to unlock with other online users on one of the game's virtual arcade cabinets.
-a brand new, single player mode, CS Mode, playable in a more desktop friendly 16:9 aspect ratio, which tells the story of the series in 200+ stages, with plenty of references to events, and music tracks, from past entries in the series.
I mostly play the CS Mode, and it's a blast. This mode has tracks from pretty much all games in the series. I love Zuntata's soundtracks, and I can't tell you how much I enjoy shooting things while listening to their kickass music.
The first time I got to a stage and got Olga Breeze (from Darius II), or FAKE (from Darius Gaiden), I nearly fell off my chair.
The DLCs just add even more "fan service" to the game. No, I don't mean of the semi-nude anime girl variety, I mean even more ships, stages and music, from other classic titles like Night Striker, Metal Black, RayForce, and more.
And to those who keep posting that Freedom track, I'll just say it: I actually like the track.
It works well in-game.