Thanks again, Blu.
1. Yes, pretty much. Obviously the amount of bytes used can vary, so the number of data blocks read from indexes etc. can vary, but this is generally not noticable and certainly not something you should worry about.
2. Yes, always store dates as DATE or TIMESTAMP as appropriate.
This reply was like an icing on the cake.
You are always so helpful... an asset to the Oracle community. It's really appreciated.