The two major travellers to India, Faxian and Xuanzang visited India from the circuitous western route, while the third one Yijing travelled by sea. Xuanzang described hardships in his journey, and crossed the western frontier in defiance of a ban by the emperor.
The Tea Horse Route, through Sikkim-Tibet seems shorter and intuitively easier to cross, since the Silk Road passes through the Gobi Desert, the Taklamakan Desert, and hostile territory, under influence of Central Asian nomads.