The long and short of it is that we only have a set amount of pages for the Buyer's Guide each month - normally around 36. Bearing in mind that we have an average of 40 new products coming in each time, it's hard enough to make room without deleting valid products, never mind listing everything else.
It is frustrating - to help counter it we've set a 5 year limit on products, although obviously, if they're discontinued long before that, they go automatically.
As Clare said, it's just not feasible - although occasionally we can help with old reviews; I've still got access to a database with 15 years worth of products and it's possible sometimes to assist with queries. It's more the exception than the rule though.
Sorry for a late reply on this - I've only just seen it! Busy creating Buyer's Guides don't you know...!
Have you stopped flexing yet by the way? I used to have a 1970s copy of Lou Reed's Transformer on flexible vinyl - true genius, you could flex it nearly 180 degrees and it'd still re-shape and play fine afterwards!