I bought 10 pieces of different timbers as a "sampler" to see what some of their stuff was like a few years ago. Nice piece of spalted beech, sadly full of woodworm that had me very worried for a couple of years...
There was also a piece of Jarrah in the same lot that I left stacked in a pile with some pine offcuts. When I came to look at it twelve months later, there was a hole a good 7mm across clean through the Jarrah, through 2" of pine, and back again through another place in the Jarrah. One very hungry and big wood-eating bug.
I never found evidence of what ate the timber, but about 18 months later I moved my workbench and found a big purple-hued beetle, dried and dessicated behind it. It was a real beasty. I looked it up at the time and can't remember now what it was, but I've seen no sign since and so I'm clear. The best defence in my workshop is the lack of humidity - I have a garage that's part of the house, and keeps pretty dry all year round.
As a result of these gremlins, I've not tried Good Timber again. To be fair, bugs can hit anywhere. They are very friendly and I'm not put off them forever. In fact, I am sorely tempted by some of their Antipodean wonders. Also in my haul was some She-Oak, which is just gorgeous. I turned some of it into a Colen-Clenton inspired marking gauge, and it really does finish nicely with oil. I'd like to make some furniture from She-Oak when I come across an appropriate tuit.
Cheers,
AG