Thanks for the input
I have a burner already. I am using the DVD drive of my slim-line laptop. I am not doing high volumes and am not concerned about speed. With inferior media, I still rarely get coasters. Which was the reason for my question. Discs I have burnt up to now have been for short-term back-up and none have failed within a 2-3 year period. I could buy recommended media, achieve a successful verified burn, lock it away for years and then find I don't have a working copy because the burns were more prone to decay. Perfectly happy though to buy a new burner if it solves a problem - like you say these days they are cheap enough.
When I said "20 years", I don't think I am taking too much risk on hardware obsolescence. My cassette tapes (not just audio but also 25 year old Sinclair Spectrum programs) and vinyl records still play OK - even 78's can still be made to work, as can punched tape if you really need it to. None of these media were quite so ubiquitous as the DVD. So I'm pretty confident of having a DVD-R player in 20 years time. Tell me that the media only lasts for 10 or 15 years, fine - I'll just re-archive and/or re-format after 10 or 15 years.
Everyone seems to focus on telling you what are the best discs to use. Fine - Verbatim DatalifePlus or Taiyo Yuden. easier said than done. I am in Europe (UK). DatalifePlus doesn't seem to be a current brand (either in Europe or on Verbatim.com). There are a variety of Verbatim products, including "archival quality" gold discs at
