Help Fusion strikes or Brilliant stars?

[CSMoss]

I'm very new to pokemon scene. Celebrations has brought me back, just bc 25 years ago I was 8 and thought it was so awesome, but never got to collect for different reasons. But what I'm asking is, will it be worth putting money into Fusion Strikes since Brilliant Stars is already coming out in February. I already have a couple Fusion Strikes pre ordered, but wondering if I should buy more when I can or just wait.

Thanks for any reply.