I'm renting this game now from gameznflix, and thought I'd throw in my 2 cents. I think it's a great game, definitely worth $30, because that would be a steal if these games were in the VC individually. But, if you're like me, a long rental will suffice, and maybe a purchase down the road when it's only $20.
I had no idea what to expect from this game, and it wasn't until I started playing it that I realized I used to play this all the time at the arcade when I was young, I just had forgotten what it was called. So it was a great trip down memory lane. I think even the first Metal Slug had good graphics for its time, and the replayability factor is high, especially if you have a 2nd player.
The games are short, but tough enough. Then again, I died so often that if I were really playing with quarters, I would have spent $40 on the first two games alone. Probably because I didn't know how to throw grenades until I read this forum.
Is this the only game that was originally an arcade game? I wish we could see more blasts from the past on the Wii (i.e. Simpsons Arcade...i wish)