I wouldn't really say that. Note that my amplification situation is a bit different; all my dynamic headphones are sensitive enough to not need dedicated amplifiers, and my Stax setup requires specialized amplification anyway (as do all electrostatics), making the headphone amps built into sound cards pointless.
Besides, I think it's a better fit to match the amp to the headphones than the other way around. Just because lower-end cards (as in anything below Titanium HD, Essence, or Claro Halo level) are touted as having dedicated headphone amplifiers doesn't mean they're capable of driving the more demanding dynamics or orthos adequately compared to a discrete headphone amp.
On the other hand, if a Xonar Essence STX sells for $150, that would be cheaper than an X-Fi Titanium HD at $100 and a FiiO E9 for $80, provided that you really do need the E9 in the first place. (Note that the Essence STX and the E9 basically have the same amplifier circuit.)
Ultimately, though, the decision still hinges on what you play. If you're into the older stuff like I am, would you mind possibly losing out on proper EAX 3/4/5 support (meaning games that use them may have completely missing reverb/chorus/occlusion/etc. effects and not sound as intended) and having to settle for virtual 7.1 instead of true 3D binaural sound?
If so, the Titanium HD is pretty much your best bet. If not (meaning you only play games with software-mixed audio where you're not getting more than 7.1 worth of positional information anyway), then the Essence STX, Claro Halo, and so forth are really good contenders.
If you don't know what sound API or middleware a given game uses, just ask me and I might know.