I never write reviews, but this stuff is so awful I just have to add a warning.. Gave this a go as it's *so* much cheaper than the Mag citrate I usually buy, but it's like a completely different substance! It should easily dissolve, fizzing slightly in warm water, and taste a bit citrusy, almost pleasant to drink - the MyProtein version is a courser powder that just sinks to the bottom of the glass. It's like trying to eat fine sand, a horrible gritty texture that can't be hidden by mixing it into foods. It doesn't really taste of anything except disappointment, but there's a slight scent of stale pond water after mixing. I hate throwing things out, but have no idea how to get through the bag!
Goes Well With:
Nothing

I was initially a little put off by other reviews stating its poor mixability, however I’m glad I didn’t let it put me off. I was concerned it’d make my shake gloopy like unmixed protein, but that’s not the case. It’s more like very fine sugar, which isn’t unpleasant at all, in fact I quite like it.    This is a welcome addition to my shakes and appears to do the trick. 

I bought a 500g bag, to use with my family. The texture is like salt, except it does not dissolve like salt, it stays grainy, like a bicarbonate soda actually. I just put it in my meals, and no problem. It does not have any taste at all. The only downside is a scoop. I personally find portions very confusing, with all of Myprotein product scoops. There should be one whole portion size scoop (not more, not less), suited for each product, so I do not have to use the super precise scale for products like this.
Goes Well With:
Everything except water. I use it with vitamin B6.

I didn't like the idea of a powder magnesium at first as it's easier just to swallow a pill isn't it? However, with the powder it is pure without stuff to bind etc. I either mix it with my yogurt in the evening or put it in my hot oat milk that I have with Cassein at bedtime. It mixes well and has no taste so I hardly notice it and it certainly doesn't detract from what I am eating/drinking it with. I am on my 2nd pouch of this and will continue to buy it.
Goes Well With:
Yoghurt, Oat milk

Since buying this I’ve added it to my daily fruit and protein smoothie. I don’t ache after exercise anymore, and the regular muscles cramps that I used to have don’t happen any more!! It has a very subtle salty taste but I think my smoothies are nicer for it! :)
Goes Well With:
Protein shakes Smoothies Soups

Brought this to help with tiredness and also restless legs, i have to say its brilliant have seen a differents since taking it.
Goes Well With:
shake

I didn't like the idea of a powder but now really pleased, no extras to bind and mostly no gelatin to swallow. It mixes well with protein powder so I can use it easily. I believe Citrate is the only way to go.
Goes Well With:
Protein powder and plant milk

Definately helping with sleep. Great value and excellent swift service. I will order again.
Goes Well With:
I mix with fizzy Vit. C lozenge as helps to mix better.

Interesting one this - I read about magnesium making you sleep better so I thought I would put this to the test. I used my watch to monitor my sleep for a week then I did the same but taking the guided amount 1-2 hours before bed.  So it seems that it definitely helps. My time asleep improved and I had more deep and REM sleep overall.  For the price not a bad supplement to add to a healthy diet ! 
Goes Well With:
Just throw it down with a bit of water. Doesn’t mix well but worth taking for the improved sleep. 

An extremely cheap and effective source of magnesium. Worth noting that this product is trimagnesium dicitrate, a cheaper form of magnesium which isn't soluble in water — this means it's tasteless, although it's like drinking sand. Much better than the other bitter or metallic tasting forms.
Goes Well With:
Water