I have tried many callers in my day, and the best by far is/was the UCaller, I have the new modle and it works a treat. The rabbit distress sound is second to none, I have had them come in from a far to this caller, its worth looking at.
Now having said the above, I think that most companys who make these callers use the same sound card, hope this helps.
Have a look at the caller on www.lractive.com.