Mach Tornado is my favorite special, period. So many uses, and so much damage can be racked up!
I loooooove Meta Knight! He is my favorite Smash character ever. Yeah, pressing the attack button and comboing like a madman is fun, but I also like to mix it up an play a bit more deceptively at times. Using agiltiy to move around, Dimensional Caping all over the place, landing an attack when they don't expect it, and then following into the air for his amazing aerial battling!
Meta Knight is not about spamming. Spamming with Meta Knight doesn't work, you have to use combos. Flow from one move to another, but don't stop the attack! All my friends and kids at my school were convinced MK was a "low-tier" character. I have set out to prove them wrong, and so far I am succeeding (my friends get so disappointed when I get a lot of consecutive wins, sometimes they just disconnect from WiFi XD LOL).