I'm almost afraid to say this, for fear of tempting the Gods, but my 310 works as well now as the day I bought it. So yes, I reckon I'd still buy one, even though the competition in this class is a bit stiffer now than when I bought it (I'm thinking particulary of the new Record equivalent which is very similar).
Coincidentally I was round at Mr & Mrs Oryx's gaff yesterday along with Tom (Wizer) listening to Simon's woes regarding his 410. As Tom says, the conclusion we all seemed to agree on is that the 310 is the original and well thought out machine, whilst the other two are versions of it with associated shortcomings.
The 260 was clearly a cut down model, with the omission of the table height lock and adjustable outfeed table obvious cost saving measures.
The 410 on the other hand is essentially a 310 with larger tables, seemingly without any upgrading of the workings to cope with the larger stresses; the counter balance springs to assist with table lifting, barely adequate on the 310, are identical and next to worthless on the larger model. Simon's problems with the feed mechanism persistantly giving up the ghost may very well have another cause, a tight or seized drive roller bearing possibly, but the inclusion of plastic/nylon drive gears seems a little low spec on a machine of this calibre.
As for getting better value by buying s/hand well I'm not sure you do really. You may very well get a used Sedgewick or similar for tha same kind of money, but you'll also have the headache of arranging transport and the uncertainty of a machine without any kind of guarantee or after sales service. When this last item is as good as you're likely to get from Axminster foregoing it is not to be taken lightly.