pokopiko
It's easy talking by seeing things that exist only in papers! But instead of sticking to the theory, it's better to compare thing that you have already tested. I tested the Yamaha in a studio PC I built two years ago. It was an INTEL PIII 650 in an Asus CUSL-2 with two soundcards, 2 Seagate SCSI HDDs and a Yamaha CRW-2100S CD-RW. The souncards were Yamaha SW-1000XG (for use with Cakewalk Pro Audio 9.0, Logic Audio Platinum v4.0 and Cubase VST v5.0). The other card was a Yamaha DS-2416 DSP factory, used for Audio mixing as an emulator of the famous O2R mdigital mixing console. This was the first time I saw with my own eyes and tested myself the Yamaha SW-1000XG, although it exists since 1998! Probably you don't know what I'm talking about since you saw some reviews based on the cards you say...
Since then, I have built a lot of configurations for musicians, music houses, DJs and Clubs that use either Editing or Automation software in combination with high quality soundcards. MAny solutions were based on Terratec cards like the EWS-88MT, EWS-88D, DMX, DMX XFire 1024, EWS-64XXL, SixPack 5.1. Others were based on Lexicon Core2, KORG 1212, MaxiStudio ISIS, RME DIGI and Hamerfall, Event Gina/Darla, SoundScape Mixtreme, Midiman DMAN PCI etc...
As you see I have many experiences to this and I can have a better opinion to this subject...
And YES, Terratec DOES offer solutions that are in the greater price/value for the money paid. And the best value for money solutions anyone can get right now are SixPack 5.1 or DMX XFire... I made my choice and have a combination of Yamaha SW-1000XG and Terratec DMX XFire since I have no much money right now to afford the Terratec EWS-88MT as a second soundcard...