I think I'm learning to appreciate some shmups

[Doctor Fugue]

Great choices. Mars Matrix is without a doubt one of the greatest shooters ever made. And that DC port is indeed one of the few home ports that is (in many ways) better than the arcade, as well as having the immense replay value with the shop and everything.

Yes, they are all vertical-scrolling 4:3 shooters; sometimes known as "vertizontal" or "yoko" orientation (of the monitor). There are relatively few of these, Radiant Silvergun is the other sublime example.

[Niode]

I love MM and GW. I've never actually played them on the DC. Just on my Mame cab. In fact GW is one of the games that I constantly replay. I'd like to get the DC version just to see the extras.