So I dug up a couple of "Cloudy Nights" owner reviews of the generic Synta 120mm f/5 achromat (which is the basis for the Skywatcher and Saxon versions I was referring to above, and is also marketed under Orion, Astroview, etc.).
http://www.cloudynights.com/item.php?item_id=2168
http://www.cloudynights.com/item.php?item_id=646
http://www.cloudynights.com/item.php?item_id=1602
http://www.cloudynights.com/item.php?item_id=1257
I think they cover the main bases pretty darned well. Overall conclusion seems quite favourable, with similar impressions to what Kevin have given for his model.
I know this is not going to be an Apo quality astrograph, but I suspect it will serve me very nicely... Almost crossed that 'decision threshold' now