A Sagárnaga agency between Illampu and Linares running the standard Cordillera Real work — a two-day Huayna Potosí, treks, and the Death Road on a front-suspension bike — with guides who get repeat customers. One review on their own page is from a Czech climber who has been up Huayna Potosí with them three times in three years with three different groups, which is the kind of testimonial worth more than a star rating.
Their own line on it is the right one: the tactic is to encourage you to the summit and, more importantly, get you safely down. On a 6,088-metre mountain sold as an easy first six-thousander, that is the distinction.