The type of cabinet can make a bit of a difference in value actually, depending on what they are, and you need to beware of certain other things. One of the last pairs that sold on ebay (item no. 330339488217) represented the change between Golds and HPDs, and they had rotten foam surrounds and HPD cones and crossovers - so were effectively HPD's. Those are the ones that went for £465, and they needed money spent on them to get them fixed.
The pair that went for £510 (item no. 120437197183) looked like a much better deal to me as they were in good nick, but they were in diy cabs which makes them slightly less desirable even though the cabs are probably at least as good as Lancasters or Chatsworths. Chatsworths seemed to be flavour of the month a while back with some pairs in good nick going for nigh on a grand, whereas Lancasters are more common and fetch less.
BTW out of interest apparently Lockwood can now recone HPDs with new cones with pleated cloth surrounds which will not rot, which is great news if you can pick up a pair of HPDs cheaply!