Eh, EAX is more or less for older games now, as even Creative admits it has depreciated the spec. Nevermind that Creatives own HW is sub-standard compared to the competition.
Best choices are:
Auzentech: Prelude/Forte; Both use the X-fi chipset, but use much higher quality parts then Creative does
ASUS: Xonar DX, Xonar D2/D2X; Does not use X-fi chipset, but like Auzentech uses higher quality parts. Emulates EAX5 through drivers, allowing decent compatability with EAX5 in most games.
HT Omega Striker; Very good soundcard that uses better parts then Creative, at a very affordable price. Lacks any EAX support.
To me, I'll take higher overall quality ahead of a few extra effects. If X-fi means that much to you, at least go Auzentech...