Everyone got his/her own opinions about Hi-Octane and thats because everyone got different experience about it.
I tell you what ... 1 baar kisi achay petrol pump say SUPER wala petrol dalwain (koi aisa pump jiss k baray main consumer reviews bohat aala hon k unn k petrol bohat acha hay - aur aisay pump bohat kum hain) ... Sirf 1 baar ACHAY WALA super kisi Achay Petrol Pump say dalwain ... Use karain.
Phir use the combination of Hi-Octance with Super ... aur phir Use karain.
Aap ko khud he pata chal jaye ga k agar Petrol achi quality ka ho to Hi-Octane ki zaroorat he nahin parti.
Main ne bazat-e-Khud bohat use kiya hay Hi-Octane in almost 3500 km ride on my CG-125 ... but finally i realized its of no use.
Haan agar koi halki/gandi quality ka petrol kahin say dalwa liya hay TABB 1 aadh baar 1/3rd ... Hi-Octane/Super ka combination daal lo. Warna koi zaroorat nain hay.