The North and South are two extreme opposites. Southerners will even add e's to words that don't contain them (for example, say cinq-e instead of cinq). The regions in between seem to vary. To add to that, it also seems to vary from speaker to speaker. Some people mush together and swallow letters and syllables to an extreme, for example.
So in short, I think you can't know because it depends on who you ask, but not saying them unless there is a liason seems to be your safest bet.
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