On the whole, I turn down DM's unless I've been speaking to them for a while. If a DM request is out of the blue, you can guarantee:
- A. They want to feed you a load of old tosh without anyone interfering.
- B. They want to talk about someone behind their back.
- C. They want to try and sell you something.
You nailed it!
I also follow the same method. If it is someone I have been talking to for a while, I won't necessarily mind dms but I can't say the same for people who send requests out of nowhere. B and C are the ones I have had the most experience with LOL.