According to PDSs available in Eastern Europe Titan SuperSyn 5W-40 and 5w30 are formulated with gr.III oil and though for SuperSyn LongLife 5W-40 and 5w30 a base oil is not mentionned at all in PDSs I don't see a reason why they should become formulated with gr.IV oils. Besides, it is not in sellers' habit to hide better stuff.
If to believe PDSs, only Titan Supersyn 0w30 and Titan GT-1 0W-20 are true syntetic oils with respectively gr.IV + gr.V and gr.V oils. All other GT-1 (Pro, Pro Flex, Longlife III) and Supersyn, including Longlife Plus 0W-30, are not full syntetic. PDS of Titan Supersyn 5W-50 says that it's formulated with gr.IV + gr.III. In reality it could happen that it's formulated mainly with gr.III.