@Heresy, no problem. Most people are useing summing to by by pass the digital bus on their daw, but if your going to use it to route signals in, it really depends if you want one with color or not. API also makes a summing unit, so if you wanted the punch of the API sound that would be another way to go too. Heres the link.
http://www.mercenary.com/api82limi.html
The Folcrom is one of the more interesting ones because it is a passive unit. It simpley takes up to 16 channels ( or 8 stereo ) and summ's them done to 2. The interesting part is you need a stereo pre amp to bring the singnal back to line level. So what ever pre amp you use, that is what color's the unit. Again see link below.
http://www.rollmusic.com/systems/folcrom.shtml
http://www.atlasproaudio.com/folcromlowdown.html
More INFO from Roll Music:
The Folcrom is a high quality passive mixer intended for multichannel analog summing of digital mixes. It uses no active circuitry and provides no gain or level controls. The idea is to control the level, panning, EQ, and effects sends of your mix from within the DAW, and send as many as 16 different tracks or submixes to a high quality multichannel outboard DAC which in turn feeds the Folcrom. You then perform only the summing in the analog domain. This enables you to maintain absolute repeatability from within your DAW.
Enjoy.