Reviews on this seem favourable, found a thread on Money Saving expert, where several people swore by them. My Uncle says loads of kids use them in the school where he works. So I've decided to give it a go, For £7.99 plus £3.95 postage, I figure this has got to be worth a gamble. Especially after the day I've had.
I searched the threads first, but only found more expensive ones from long ago. Hope people find this is a worthwhile offer. I'll let you know if mine works!