Both of these micellar waters claim to cleanse, smooth and be suitable for sensitive skin. They're both suitable to use on your eyes, lips and face and are described in pretty much the same way, on the back of the packaging. I like to use one of these in the evening to remove my makeup with a large cotton pad and my face always feels cleansed and fresh. At first I thought I would have to wash my face after using it but they both do a great job of removing my makeup, even mascara and eyeliner. I usually use 2-3 large cotton pads just to ensure my face is completely free of makeup, so I'd advise you buy some of the large cotton pads or some facial cloths to avoid having to use an excessive amount of tiny cotton pads.
So, which one should you buy? Well, strictly speaking, I don't think there is a whole lot of difference between the two, which isn't surprising as L'Oreal and Garnier are actually owned by the same company. If someone handed me two cotton pads with them on I don't think I'd be able to tell the difference. However, if you're wanting the one that's best value for money then go for Garnier's offering, as you get 400ml for £4.99 whereas with L'Oreal you only get 200ml for the same price. Overall, I think these are both worth the money as they both do a satisfying job.
What do you think of micellar waters?