[LAU] Headphone Amp vs PCI/Ext card

I'm thinking about getting something like the below to optimise headphone monitoring quality. Can anyone suggest a more generic all round (onboard) useful device with at least similar specs ? (and obviously works well with ALSA) http://www.head-direct.com/product_detail.php?p=11 Power consumption: 2W (quiescent), 6W (MAX), 110v Adapted load impedance: 32-600 ohms Max output: 1000mw x 2 @32 ohms to 64 ohms 250mw x 2 @ 250 ohms 120mw x 2 @600 ohms Power bandwidth: 6Hz 80kHz (+0/-3dB) THD&N (at rated output): 0.004% SNR: 98dB Output voltage swing: 10Vrms Input impedance: 10Kohms Dimension (MAX): 112mm(W) X 67mm(H) X 185mm(D) Net weight: 1.20kg (2.64lb) DAC section: Power consumption: 1W Supported digital formats: 16bit / 20bit / 24bit @ 32khz / 44.1khz / 48khz / 96khz Optical fiber(Toslink) & coaxial(RCA) 8x oversampling digital filter Total distortion: -96dB Dynamic range: 106dB SNR: 106dB --markc