At the risk of simply pointing to someone else's post and saying "yes, I do this and you should read this if you don't", Andy Kramek has a great post about Access and Assign methods can be useful!
I use Access/Assign methods probably not as much as I should and his post pulls out some examples that I hadn't thought of before:
a) to create form objects that don't already exist (as in THISFORM.oDataManager, etc). This means you don't simply do a THIS.AddObject() to a form but rather assign it to a property la THIS.oDataManager = CREATEOBJECT("datamanager")
b) Running code by using SetAll which does call the Assign method.