All of them? my pair is great no problems at all (two years old I think); very strange and good reviews elsewhere
Ist pair went squint in less than a week, the other two pairs over the next two months.
What I have found with Liddles and check for yourself, they often list one "item" and actually when you go to buy the "item" there are several different types in the box/shelf/table, all of possibly differing qualities.
For example, I have a superbright single LED head torch from there that I bought around 2001-2 and in the same box they were selling headtorches that looked the same but had bulbs instead of LEDs. Now the head torch is bril, it's the best head torch I've ever owned and I still have it and use it(much better than any petzle I own), but if I had bought two or three without checking, then they may have been different.
I love Liddles stuff but sometimes everything is not as it first appears and you need to check and see if you really are getting a bargain or not.
WS