Anything over £15 including postage is technically subject to customs charges - VAT over £15, duty over £135. The rest is down to how the carrier and customs deal with it.
We recently imported some parts using DHL as the carrier. I would think by the process I was part of, DHL have some form of electronic arrangement where they collect the duty on behalf of customs. Its then down whether the package is spot checked. I know mine was not spot checked as DHL said I would be notified if it was, although it did look like at some point that the package was inspected as it was resealed in DHL tape and a label attached to say it had been inspected.
I guess that the method that Jeda use is not as efficient and/or their customs declarations are not as robust so their packages come under a bit more scrutiny.
Yeah I've had to pay customs charges for goods from the US & Canada before, it's fairly normal. This one just seems to have dropped in to a black hole though where Parcel Force are saying they don't know anything until it's back in their hands.
Just curious really whether I've been particularly unlucky here or if there's a general hold up at customs.