Yes, it is worth to buy the Falcon Mace 
You see a falcon mace (Atk:11 physical + 41 energy, Def:33 +3, club fighting +3, protection energy +7%). It can only be wielded properly by knights of level 300 or higher. It weighs 68.00 oz.
As you can see by it's stats, it is a strong weapon (52 atk is decent, plus 3 melee skills), and it is also the only Energy-based club weapon.
Therefore, if you intend to hunt at places like:
- Juggernaut Seal
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- Plague Seal
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- Asuras
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- True Asuras
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- Prison
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- Falcons
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(Cobra Club deals more elemental dmg, but lacks energy resist) - Pumin Seal
(ignore Hands, as they runaway fast) - Deathlings
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- Banuta
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And many others.... You will need a Falcon Mace to deal the most damage you can!!! Just like Sword players NEED a Gnome Sword!
And, luckily for you, it is the cheapest Falcon Weapon, since there are not too many players using Club. So, your investment isn't as big.(+-2kk in Solidera ATM)