Finally! I have found a type of Magnesium that doesn't give me a splitting headache, and make me run to the loo!
I bought this to help with my sleep quality, and I haven't been disappointed - using my Apple Watch to track my sleep, I can see that I'm getting more REM sleep than I used to, which is great. Pricey, but recommended.
Not keen on the powder form, since it doesn't taste great, but whatever.