Thunder Force IV is trully f**king awsome and Hellfire is pretty darn good to. My favourate before I got these today for my megadrive was Zerowing (yes I did buy it before the whole "all you're base!" thing) and I thought that was a pretty darn solid shmup but I feel TF4 wins the "best shmup" crown now.
Saying that I did also buy more megadrive games. I finaly got a copy of Sonic and Knucles even though I own Sonic Jam on the sega saturn. I also brought another 6 or 7 games but the two that intrested me most were comic zone (awsome game) and another shmup which i've not tried yet called Gynoug which judging from the back of the box, the graphics look awsome, I'll play it after I complete TF4 and HF

Anyway I thought I'd declare my love for the sega medadrive (last count I had over 50 games for it, proberbly more now) and it's shmups.