Quattro Pete,
Most probably Castrol Longtec is the same GM stuff or a very similar to it, but not a cheap version of Formula SLX. There are plenty of cheap oils from other manufacturers here.
As I know there were numerous issues with Castrol 0W-30 gelatinization caused, according to OEMs, by poor gas quality. Given 30K and 50K intervals allowed in new Opels and Saabs, the oils used in these GM cars should provide a huge quality reserve which is based on an appropriate base stock and additive chemistry. Apparently it's expected that GM stuff may solve a.m.problem.
As for selling LongTec only in the former Eastern Europe (former because now business considers Russia, Ukraine, Belarus and Moldova as Eastern Europe, but Poland, Czech Republic and Hungary as Central Europe). Think this was made mainly for marketing reasons. If we visit Castrol sites in Russia and Poland we shall find interesting situation:
- Poland: there are both Castrol stuffs, GM and Longtec, but LongTec description does not contain PDS;
- Russia: there is no Castrol GM, but Castrol LongTec is presented with PDS.
In 90th Castrol made a lot of money in ex-USSR. According to some estimates Castrol had more then 50 % market share in the 1st half of 90th and around 30 % in its 2nd half mainly thanks to synthetic oils. So, no doubts this market is very important for Castrol (like for BMW: Russians were the first to whom BMW made presentation of its new "6" model !). Some special products like Castrol GM or LL01FE are usually more expensive or positionned like more expensive, and if they're to be sold via car dealers only, their sales volume in Eastern and Central Europe will be quite limited. Therefore, offering GM under LongTec Castrol will be able to sell higher volumes and avoid undesirable price questions. Think the only difference between LongTec and GM stuff, if any, will be in a quality control.
http://www.castrol.pl/webs/servlet/webS?action=page;osod12
http://www.castrol.pl/webs/servlet/webS?action=page;osod20
http://www.castrol.pl/webs/servlet/webS?action=page;osod
http://mail.castrolcis.com/homepage.nsf/Home?OpenPage