Models or DGNS which is better?

I like to use separate DGN's for each corridor. Separate DGN's for each superelevation, and for Geometry.  There could be some combining for things like small corridors or simple geometry but seems best to separate them.  ORD is creating and managing models and 3D models so I do not like to get to much going on in one DGN.  Additionally multiple models allows for multiple users to participate in the Design.  Then there is always the corrupt file from time to time.  If my data is in separate DGN then each container has safe data.

Multiple DGNs is the recomennded way to work, and it's my preference.

I keeps the file from getting too large - by the time you have all of your design and your corridors and your terrains and everything else, I think that would make the file slower and less stable.

Mike also mentioned a couple of good points, and the big one for me is that keeping the data federated means that more of the data is protected from corruption. If everything is in one file, and something happens to that file, everything is lost. If things are kept separate, we'd only lose that one chunk of data while everything else is untouched.

That being said, There's wiggle room depending on the project. For something small like a single cul-de-sac, I would probably keep that all in one file. I keep my medians in a separate file from my roadway, but I don't have a separate file for every median; the same with driveways. My roadway drawing may have more than one corridor (backbone, sideslopes) For longer projects, I try to keep everything split into one mile regions so I might have RoadCorridorR1, MediansR1, DrivewaysR1, RoadCorridorR2, etc.

I am convinced that having things split up is the best way to do it. I makes more drawings, but it also makes it easier to reference only the parts I need while protecting my data from getting all hosed at once.

There is a best practices document that was written for SS3 or Ss4 that is very specific to the Opens Roads workflows. For projects of any size, it is recommended that you use separate files for many workflows - they call it federating the design. Too many civil elements in one file can trigger reprocessing of the design at the drop of a hat.

To be honest, I'd never even thought of having separate models for terrain, geometry, superelevations, and corridor (etc.) all in one dgn but it's an intriguing concept. Perhaps worth testing.

As all the other comments have suggested, we also keep all the models in separate dgns. It certainly makes the files more manageable and the likelihood of an unexpected crash losing your entire design mitigatable.

that is more or less my own concerns but since im working on trial/testing projects anyway i will go ahead and try it out. After some more thought on the subject i think im going to keep geometry separated. the corridors, terrains, and earthwork are all too co-dependent to make much of a difference in the event of file corruption. i will repost here with results if any are promising.