I just picked this up. 4,000 yen and a 61 meg download.
Really this game should be 2,000 yen. I can't believe the price, it will probably go down.
It's made by a company called Pyramid. I've never heard of them before.
It starts with an arcade mode, two secret modes to unlock (from looking at the instruction manual they are mission mode and burst mode), a view mode and an options mode.
The game looks a lot like G. Darius but with sharper graphics. Imagine the beams and shots from Gradius V.
The bosses are small after playing G. Darius. They can fit in the screen and do all the familiar Darius things and shoot the familiar Darius bullets. Nothing new so far.
The music is AMAZING. I'm sure this is Zuntata and the game is worth buying for the soundtrack. It's got the weird choir arrangements and spacey synth sounds. Very atmospheric.
The gameplay is similar to G. Darius, but no capturing and the levels are much shorter.
In the manual there is a lot of story (2 or 3 pages) and in the back is a history of the story of Darius. I never played Darius for the back story, so this is all new and somewhat cool. Story wise it looks like the games go in this order: G. Darius, Darius, Darius Gaiden, Darius 2, Darius Burst.
It definitely feels like a Darius game, but smaller. It's nice and would be a recommendation at 2,000 yen. I'll play a bit more and post, I've only played through it once so far.
EDIT - There's a lot of great information about the game in the shmups.com forums, a lot to read through, but here is a link from the ninth page onward:
http://shmups.system11.org/viewtopic.php?f=1&t=27798&start=240
Looks like Burst Mode (which you have to unlock) is a lot of fun. Can't wait to play it.
I've played through a few more times and unlocked a ship and the mission mode. Game is pretty fun so far! Not quite as rad as Darius Gaiden or G. Darius, but a lot of fun.