My real world experience with NIC's is this.

Realtek, DLink, any cheap cards are most likely made by a company called Accton, an OEM manufacturer. Have you heard a saying, "You get what you pay for"?

I actually use a Realtek at home, but in a work environment no way. One reason only, they tend to do a little too much broadcasting.

I myself have had issues with 3Com products, so I switched to Intel cards. The main reason i use Intel is administrative, one floppy disk for the driver, lets see 3COM do that with all the 3C90x models.

Thats my 2 cents (Canadian money not worth much).