for £15 it is hardly breaking the bank.
But don't expect the quality to be high.
Very likely to yield soft images, distortion and lots of CA.
Though it may not be too bad in the centre of the image.
There are high quality close up lenses though - such as from Canon 250D and 500D. The quality from these is quite good. These are actually composed of 2 glass elements, and multi coated, just like proper Canon lenses. They are not cheap though.
All these images were taken with a similar high quality, 2 element Nikon 6T close up lens - sadly no longer in production.
http://www.flickr.com/photos/lozwilk...7603266363366/
Similarly any of the flower macros in here were with that lens
http://www.flickr.com/photos/lozwilk...7603270815461/