Philips made the PCS1000, PCS130 (which takes the optional PCS150 color controller), and PCS2000. The PCS130/150 and PCS2000 were also sold under the Paterson name (the PCS130 was sold as the Paterson PCS2500; the PCS2000 name was used under both brand names). There's a Yahoo group devoted to these units: http://groups.yahoo.com/group/tri-one/. The PCS1000 was a B&W model with a fluorescent light source. The PCS130 was a condenser model and the PCS150 added an additive (red/green/blue) light source to make it a color model. The PCS2000 was a diffusion model with an additive light source similar to the one provided by the PCS150. These were made in the 1980s, but I don't know exact manufacture dates. I'm not sure about the PCS1000, but the PCS130 can handle up to 6x7 format (given appropriate condensers), while the PCS2000 can handle up to 6x6 (given the right mixing box).
A Durst I don't see mentioned is the C35, which is a low-end diffusion model with built-in yellow and magenta filters. It's usually equipped only for 35mm negatives, but a kit to enable medium format (6x6, I believe) support was available, but is hard to find today. This was another 1980s model, but I don't know the exact manufacture dates.