best bang for your buck TFCs
1. Insecticons
2. Soundblaster
3. Perceptor

TFCs you're required to buy to complete the set ... but kinda feel ripped off
1. Optimus Prime - $170 for 1 figure?!
2. Megatron
3. Soundwave

Prettiest TFC not mentioned above
1. Minibots
2. Sideswipe
3. Hotrod or Stepper