I haven't personally bought anything from there, but I've only heard positive comments about Good Old Games.
Before applying 1.8.26 it would just say 'this application is not designed to run on a 64-bit system'.So I will passively look out for an Underworld (or Gold version if cheap enough) box or download but for now I have given up on Sacred Plus. Schot and I were discussing and he could not get Plus to work either without Underworld installed (and patched up to 2.28).I did finally get the 'driver not loaded, contact Henrik' message after I applied the patch. So I have found that I cannot get Sacred Plus (1.8.26) to run on my PC.