Dranzer gt and dragoon gt

Dragoon gt and dranzer gt have always been my favorite beys they have a sweet look and great feel and they are very valuable but what makes them so valuable they are not different then then other beys except the fact that they have turbo but other turbo beys are not very expensive what do you think makes these two beys just wonderful to have
I have both myself i dont really dont know why they are so wonderful to have?
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