I take it you are not familiar with Fuchs Super GT & Petromin Ultra7, both can handle 5000kms of pakistani environment and offer similar properties to any synthetic available in PK. Do note that even mobil1 has a hard time suspending particles till 10000kms. so using any oil for long drain intervals in PK is likely to cause more harm than good.
BUT, i do agree that if you can afford regular changes and the high prices, then you should go for a synthetic like Mobil1 or Zic XQ as they are both very highend oils.
it's a misconception that these numbers mean how thick the oil is, yes it serves as a guide but there is more to oil than just the SAE rating. what is more important is the pour point and the flash point. this topic has been explained by both myself and SKZIC a few times already.
though i'm allowed to advertize my own product i think i should be fair (something i have tried be always on PW) and i find it unfair when my competitors get bashed for no reason or if someone has their facts wrong/askew about oils.