I got my boys the old TRANSFORMERS show on DVD. The show was always conceived as a toy-selling medium, of course, but I remembered watching it in my childhood, so I was watching it with them a bit. I think Soundwave is the spookiest of the Decepticons -- not only does he have that cool synthesizer voice, but he's big and is always lurking about creepily, and lacks any discernible personality -- all terribly creepy. Megatron's a blowhard, and Starscream is a shrill buffoon, but Soundwave is the most inscrutable, and, therefore, the most alien and malevolent-seeming. You don't know fully what Soundwave's up to, only that it's no good. One thing that always bugged me about Soundwave is that formidable-seeming device on his shoulder. I had always wanted him to fire that sucker, which could be a gatling gun-type weapon, or, perhaps, a missile launcher. But he never, ever used it. It irked me as a kid. Even as a type of microphone, it never showed up. I guess they just put it up there on his shoulder to make him appear more badass.
My favorite Decepticon was Shockwave (although Starscream always amused me, with Cobra Commander's voice and all, and his endless scheming against Megatron -- the "Odd Couple" relationship between Megatron and Starscream amuses me). My favorite Autobot was Brawn. B1's favorite Autobot is Optimus Prime ("He's very strong, and he agrees with some stuff and sometimes he doesn't."); his favorite Decepticon is Shockwave (B1 says "He looks interesting and cool, and when he talks, his yellow dot eye flashes"). B2's favorite Autobot is Bumblebee ("Because he's small.") His favorite Decepticon is Thundercracker ("Because he's BLUE!")