Design Question

[Brian Maher]

Hi Folks,

I have a design question and am looking for input on the best way to 
handle things.

First, my app will be for OS X only so I want to do things the OS X 
way...

My app will need to download and store a list of items from a web site 
(around 25,000 items) and although it will be likely that all users on 
a machine will access the same site it is possible that one or more of 
them will access a different site.  My design question is this ... what 
is the best way to store this information?  Going back to the web site 
each time is not a good solution (the info is very static).  This data 
is going to be used to enable the downloading and reading of other 
information (think pointers) so I will need to have quick access to it.

My thoughts so far are as follows:

1) The app goes into /Applications as normal and will be distributed as 
a .dmg file using a normal OS X .app bundle.

2) The downloaded data will be stored in a subfolder of each users 
~/Library/Preferences folder (downside=duplicated data).

3) The data could be stored in an external stack (with custom file 
extension or no extension at all) for easy access.

4) The data could be stored in the standard user preferences file for 
the app (using the 'defaults' command to read/write).

5) The data could be stored in an external database of some kind 
(single user).  The downside is the cost (i.e. this will be a very 
inexpensive application).

Any other thoughts on how to store info?

Thanks, Brian