Most modern French fiction uses the
approach which is absolutely fine until you reach the follow-on sentence. So if you have,
- Let's go swimming. The water temperature... |
|
until you get some way down the track (maybe with the need to backtrack) you don't know whether 'the water temperature' is something she's saying or something the author is now writing. It's a source of constant annoyance.
Unless you're prepared to start a new paragraph after each piece of speech, it's a pain. I would always favour the use of (single) quotes anyway.
Chris