I understand that in order to benefit from ArcGIS spatial datatypes (ST_GEOMETRY, versioned geodatabases etc.) ArcSDE needs to be installed - and with the 10.1 client it is automatically installed (two-tier client>>DBMS, see here.
However, I'm still trying to figure out the benefits of connecting an Esri front end to PostgreSQL (or Oracle). Is it purely back-end benefits, such as scalability /performance / redundancy / DBAability, or are there any extra front-end features offered by a PostgreSQL / PostGIS setup? The Esri help does not seem to elaborate
FYI, I'm pretty much a database newbie who is designing a GIS dissertation aimed at illustrating why Postgresql / PostGIS / QGIS is more scalable / flexible (and cheaper) than ArcGIS / any database, so must also consider above scenario, which I can't afford to implement. Any links on this last point, especially regarding workflow (e.g. not having loads of shapefiles cluttering everything up) most welcome. d.