We recommend the 6-day Machame Route if you have pre-acclimatized to the high altitude and feel confident to complete your climb in 6 days.
In such case, and if you don’t mind sharing your climb with many others, then the 6-day Machame Route will be your best choice. It boasts some of Kilimanjaro’s best scenery and has the best altitude profile (hike high, sleep low) of all 6-day routes.