Best path for Core Data implementation

Hi all,
First post so pls go easy!
I'm a seasoned Windows/Web App developer who has recently (3-4m) discovered Mac, Cocoa and Obj-C. I've been buried in Apple docs, Hillegass and Dalrymple books for some time now trying to get to the point where I'm ready to build the Cocoa project that I have in mind, which looks to be well suited to a Core Data based Application driven by SQLite. The data model is reasonably complex with around 10 inter-related entities which must retain data integrity.
Anyway, onto the question... historically I would have built a class library to encapsulate the use of the data model and accessed that class library when events fired to do what needs to be done. The Cocoa solution appears to support this - presumably though creating my own framework that is then referenced by the Cocoa application. I can see though that there is another path where I skip the encapsulation and build a Core Data based Cocoa app directly.
At a high level - is there a preference between the two approaches?
The latter seems well documented/supported but I am synically thinking that is because it is more straightforward and clearly faster, are there other advantages such as performance.
For background the app when running will follow similar form to Mail.app in terms of multi-view with some data tables and custom views in play.
Thanks,
Chris

Hi K T - thanks.
Bottom line I think is that encapsulation is a safety blanket that I probably need to let go of. CD ticks boxes on a theory level, subject to implementation not being too heavy it seems like the logical step. The only consideration was to encapsulate a framework built on the known methods, then move the framework to CD under the covers when ready - that seems a bit gutless though and almost definitely inefficient time wise. I guess that there is little point in encapsulating CD from the outset - feel like it just adds unnecessary work in addition to some degree of performance overhead?
{quote}Are you looking for flexibility or performance, by the way?{quote}
Performance - the data model is unlikely to change once bedded in beyond addition of properties etc very infrequently. The app is likely to need to handle many tens of thousands of rows of data (albeit small in terms of data volume per row) for some users, and my conclusion from the documentation was that SQLite is the most appropriate route if committing to CD where data volume and/or relationships are plentiful. Is that a fair assessment?
{quote}Are you looking to mimic traditional application interfaces or to adopt trends that are currently unfolding?{quote}
The app I plan to build desperately needs to be brought up to date - possibly even beyond the advanced UI that AppKit seems to offer by default IMO. That said I don't want to overcommit on the extent of the build, but I do want to turn heads without just slapping coverflow or similar in for the sake of it. If you have any references or examples for doable leading edge UI design on OSX they would be gratefully received.
Thanks again for your help - really appreciate it.
Chris

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regards
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UK

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