Is it worth investing in a new deck now, or should I wait for Zexal World and Xyz monsters? My Blackwing deck is getting wrecked by everything in the Turbo Duel Grand Prix (I can't even keep 5 Stars)and it did awful in round 2 of the KC Grand Tournament even with a better skill.
Assuming your BW deck still don't have 3 Simoon, 3 Whirlwind, 1-2 Zeph, 2-3 Bora & 2-3 Gale.
I recommend you try get whatever was missing from the above and complete the BW deck first. BW is still good as of now but it is glass cannon.
Besides, I don't expect any good Xyz or Xyz related card from the first few box when Zexal is released. Usually the good one might come like 4-5 boxes after.
You cant keep too many gems anyway.
I don't think going in a box just bcz ur deck performed badly once or twice is a good idea first u should try and fix your deck's problems and try getting the cards that will help u doing this....
Me personally I'll wait 4 zexal and I think that's the best option tbh but if u really want 2 but a new deck go with shiranui