Kit,
I commonly change/add columns to one of my deployed projects which uses .netTiers heavily, Im not sure I mean 'what is affected', could you elaborate on that a bit?
As far as your second question, It's really a matter of needs/requirements/and tastes. The domain model is quite similar to what a lot of DAL devs have worked with before, so it's where I started. The service model is quite elegant, IMO, but I have yet to use it in a project so I can't speak with authority on picking one or the other.
HTH
evo
http://www.jheidt.com
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Member of the .NetTiers team
http://www.nettiers.com
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