Allegro / Expedition

How bout this for starters. ....

Let me start by saying Mentor DXDesigner is a pretty good tool, but....

Allegro is much more flexible tool -> Expedition (iCDB flow) is much more rigid (can pull parts from only one library - building and using quick-turn pre-released parts is a pain because everything has to flow through one library)

Allegro's toolset is simpler/more refined

Allegro has 1 environment for doing pcb design, documentation and generation of mfg output.

Expedition has three design environments (Expedition/Drawing Editor/Fab Link)

Each Expedition environment spins off a multitude of additional files and folders which are linked to its own unique format of the Expedition database.

Each Mentor environment must be kept in sync with the main Expedition database. (its a pain to keep in sync - has bugs).

Operation in each Mentor environment is slightly different compared to the others - causes confusion and hard to learn 

Most of Allegro functionality and command options are accessible from mouse clicks via context menus and getting information about an object is as simple as hovering cursor over an object -> Expedition seems to require many more mouse clicks to get the same results....Example: Many Expedition options for interactive editing require supplemental keyboard strokes (alt key/cntrl key) while in a command to get the full array of options. In Allegro, they're all right their by click of a mouse button.

Allegro's file structure is simpler and more efficient -> Expedition much more structured and rigid.

Allegro's has one design file (.brd) -> can be moved anywhere independent of where schematic is -> and is completely self contained (libraries can be recreated from the one file)

The Mentor Expedition database is so closely tied to the schematic (via the iCDB) it cant be moved independently unless you go though another process (undocking).

Mentor iCDB (the link between schematic and layout) can present sync problems between schematic and layout. In general Mentor is much more complex to manage.

Once Mentor DX/EX design container loses links with the ONE LIBRARY you cant forward annotate until you link it back up.

Typical size of our Allegro/Concept design container < 100 GB - Mentor design containers can grow upwards of 400 GB (related to the spin off of multiple files associated with different design environments.

Wish I had someone to point these things out before....I could go on but you get the idea.