As you can see, this picture was taken right after i had finished doing it and the stripes stand out loads. I did however think that it was a bit of a con that you had to buy the magnet separate from the nail polish, and the magnet cost an extra £3. I have now noticed that other brands doing this are selling the magnet and nail polish as one, which makes sense.
Obviously you only need to do one coat of the nail polish and then hold the magnet over your nail for not too long, about 20 seconds i think, because it dries really fast. I did notice that after a few days the colour and stripes don't seem to stand out as much but it might just be because i was used to looking at my nails and depend on the light. I'd love to try some of the other colours and other brands, let me know if you've tried a few colours and which ones you found best.