So I'm just now really getting into this genre, I got Fast Striker on Dreamcast and it just kind of got the ball rolling. Currently playing Jamestown, I saw a mention of the Gundemonium series on Steam but not the Exceed series. Are those any good?
That same site is also very good for imports, with prices a fair deal better than most Ebay listings. I can't comment on most of the games from that list, but Warning Forever is a good bit of fun. Sort of like a twin stick boss rush without the second stick (a description I can only hope will make more sense upon playing)
Kodeen: The best stuff you can play on PC is arcade ports via MAME, but you should play Tumiki Fighters. It's really good. Pretty much the only PC native shooter I have put a decent amount of time into.
One interesting thing about it is how much your playstyle and tactics change once you get better, and how they change again once you get a feel of how the scoring works and spot some subtle details of how the mechanics work. I remember still getting "aha!" moments after having played the game for 10+ hours. It's a really fun game to figure out, so don't watch a youtube video and deprive yourself part of that pleasure.
I grew up when shmups were all the rage, so I always have a soft spot for them. Muscle memory is a strange thing; I keep hearing about how these Cave shooters are so hard. Yet almost 20 years since I last played R-Type I could beat Dodonpachi on my iphone in one setting (on medium arcade admittedly).
The Dreamcast really impressed me with the quality and variety of it's shmup collection. Since I didn't own one at the time, I'd occasionally see an amazing in-game photo of a 3d shooter online and pause to reconsider getting one. Now that Dreamcast emulation has reached a level where you get perfect response times and no glitches in most games, I've located and collected two (used) great titles which I thought might be relevant here:
Best shmup ever.
Very innovative game progression mechanic where instead of continues you get separate level paths every time you die.
Best shmup is Audiosurf.
Just saw this:
Exciting news! I love the aethsetic of this game, was not expecting a PC port.
On Wii there is a disc called 'Ultimate Shooting Collection', which has Karous, Radio Allergy and Chaos Field. It costs about $15 for a new copy, whereas those three games would cost $200-$300 for the Dreamcast versions.
Anyway, PC games. I was looking at Steam and noticed that Capcom has published a few of these as well. I'll have to look into those as well.