Sorry for this going off thread but..
SMP - apologies for the way the sub got to you, however I think your description of "rattling around in a cardboard box" is OTT, I feel the sub was packaged correctly when it left me but must have been mistreated / re-packaged by the courier. I would never just drop a sub in a box and send it - not my way of doing things. To ensure this does not happen again the Strata will have to be collected or I would deliver it.
Dan - I lifted that description from the guy that sold me the upgraded High Level cable - I'm not an expert on earthing but it comes with a phono conenction rather than the standard 'black' earth cable - it did make a positive difference to the sound so that's all that mattered to me.