Ok I got one of these and it's built up and the epoxy's drying as I type, I haven't animated anything with it yet but I have had a little play. I've seen a lot of posts asking about them so I hope I can help somebody make the decision to buy one or not.

So here's my experience with it.
I payed my 80 quid on Tuesday and the package arrived the next day.
the box contained all of the bits as well as instructions for making the armature at about an 8 inch scale.
The joints are fairly thick, so if your character needs Jack Skellington-style skinny legs, it's not going to be possible. The character I'm making is just a fairly standard man, so that was ok.

Cutting the rods to size was a pain. I tried with my own regular tool shop hack saw and it was taking forever and pretty much ruining the thread. Luckily my Dad happens to be a Goldsmith jeweller, so he had way better equipment and managed to get them all cut for me in half an hour.
Putting the bits together was fairly simple and quick, it took about an hour, not including the time the thread lock took/is taking to set properly.
Wiring up the hands was a bit tricky, but eventually I got them done and shrink wrapped, I'll be building them up with liquid latex later.

All in all, it's turned out pretty good, it's way sturdier and smoother than my wire armatures and the helping hands one I made(never again!    ).
For a regular male puppet it works well, it doesn't suffer from double-joint-syndrome because it has special little bits you put in half of the joint that locks it, and the shoulders and toes are well catered for.

However, if I had actually bothered to look them up beforehand (because I assumed freelance-made armatures would be expensive) how reasonable Tom Brierton's armatures were, I'd have paid the extra £20 and gotten one of his, because I've heard nothing but great things about them. http://www.tombriertonarmatures.com/

Long story short; The one I got is really good and just fine for what I need it for. But Brierton's armatures look better and they're not all that much more expensive.