Firstly, wait until there is a sale on expansions… never pay the normal retail price. Keep an eye out next month, there may be sales again like last year. Check the retailers in this sales thread. Generally they will have lower prices than the BFD store.
Secondly, you decide for yourself by going through this FXpansion Soundcloud link and listening to the audio examples from the BFD expansions.
You may also be interested in some of these Sonic Reality expansions for BFD. There are some good ones and they are currently still on sale.
These are some of my favorites that I own, but they’re geared more towards rock and metal and may not be the vibe you’re looking for.
Horsepower
Modern Retro
Oblivion
Dunnett Ti