Decent if it fits you well
I have an Exos 46 and love it for loads between 20-25lbs. Unfortunately I fall right between the medium and small size. A bigger pack was needed for winter and longer duration trips. My hopes were that the Exos 58 would be ideal given my good experience with the 46. For some strange reason, I found that even with the same size frame, the 58 fit differently and was not very comfortable with loads in the 35lb range. It was doable but felt that the pack would be pushed to the limit if overloaded for long stretches. Durability would concern me in the long run with more than 35lbs. It sure is light though compared to the 70L pack I ended up having to get!