Well, the Ritek G05 is a bad DVD model - a lot of cdfreaks used it a few years ago only to find the discs scanned like Taiyo Yudens when burned and were compatible with everything, but suddenly became unreadable within a few months. I wasn’t around (here) at that time, so I have no first hand experience - but this disc model is about as stable as a house of cards.
I am not familiar with the Azerbaijani market, but generally speaking there are a small number of media types that I have generally high confidence in - note that Taiyo Yuden is losing some of this because of the “packed” in China nonsense you will have read about elsewhere here.
For DVDs - anything by Verbatim (or Mitsubishi Chemical Corportation or Mitsubishi Kagaku Media) (all the same company)
For CDs - despite the recent problems you will have read about Chinese Taiyo Yudens, as of this time I am still confident of TY’s [B][I]Watershield[/I][/B] Printable CDs. That may change though if the standard of that falls in the same way that Dolphinus_Rex has found in the Silver Lacquer TY CDs.
I know of two online shops that sell these high quality medias worldwide - it might be more expensive than what you find normally in Azerbaijan, but if your data is important you might want to check these links out.
A small media seller in Connecticut, USA, this shop sells a very wide range of blank media - much of it Verbatim and Taiyo Yuden, which allows you to buy in some cases as little as 10 discs! GenesDTP ships worldwide and the owner really knows his business!
A worldwide media distributor based in Kobe, Japan, nikonekobaby sells retail products from Japan, such as “That’s” branded Taiyo Yuden, “Mitsubishi” media (which normally retails as “Verbatim” in the West) and a few other Japanese brands.