Here's the scenario:

One host application that can be connected to either Access, MsSql or MySql.
This is decided at the point on installation and won't change.

There is a portable application, 2003 or Mobile 5, not sure which way to go
yet, but this application needs to take data from either of the above
platforms and interogate on the portable. This, for the time being, will
all be batch, not RF.

The only way I can think of to make this work for all three database types,
without three different applications is as follows:

Write the portable in net 2005, using the MsSql CF client.
From the host, export data into test files, send the files to the portable
and them import to the mobile Sql server.
Collected data will be stored in a text file, send to the host and import
through a lengthy check routine.

The amount of data to be transfered from the portable to the Host shouldn't
be too much of a problem as the users wont be collecting a large amount of
data.

The problem is going to be the amount of data sent to the portable, this
could be several thousand records, each containing a lot of data. I'm
worried about the speed mainly.

Has anyone done similar or have any suggestions?

Cheers,
Tull.