They have always come up trumps with me. Although my first head torch was bought while they still offered lifetime warranty they now "only" reckon on lifetime being 4 years. However they have replaced with no quibble with any problems. Latest good news story was an email from me to say my P7.2 was playing up...email exchange to describe more detail...next day a new battery and switch module dropped through the door and P7.2 up and running again.
Unsurprisingly I have bought five of their products...the first one was replaced when the cable at the hinge went after a couple of years...3 years after that it went again and I soldered it up and a couple of years later when buying another I casually mentioned that I had repaired the first one...they said "it is out of warranty and we no longer make those...but we do have a current model that someones has returned with a damaged battery box...would you like that?"
I have purchased a few of their torches and a headlight and have found them to be very good products, if you are going to purchase, beware of EBay as there are a lot of very convincing fakes being sold on there apparently, When these stop working and are sent back to the company, you obviously have no warranty. There are a few videos on YouTube showing how to spot the fakes.