It's on sale for 400 MS points this week. I played the demo and it was pretty tough, but overall I hear it's a great game despite the difficulty curve. Also, for 400 MS points it's appears to be one of the best purchases at this price point. Any opinions?

I would since it's only 400 points this week.  If it goes back to 800 then you probably wont buy it.

I got this game a couple of months ago. Spent some time with it and was able to beat the first level, never got past the second. Super hard, but still fun. I also liked the music.

Not that i've played it, but based on reputattion alone i'd say it's probably worth experiencing, especially at that price point.

The only acceptable answer is yes.

ABSO-FUCKING-LUTELY!!!  Ikaruga is an INCREDIBLE game with tons of replay value.  I had that shit on Gamecube, but unfortunately, my car needed new shocks and struts...and I needed to do some clean-up on my collections.  I feel shitty for selling it, but I know that I can pick it up WITH ACHIEVEMENTS ON IT over XBLA.  = D