I have a 2013 Atlas Carbon, so this is a comment on Devinci bikes in general. Having said that, they share the same split pivot design and both have the Carbon front/alu stays. They aren’t the lightest of Carbon frames, but the construction is solid. In 18 months of riding I’ve had to replace the two bearings at the top of the seat stays, and nothing else. All of the cable routing is external, which some may not like.
I particularly like the robustness of the mech hanger integrated into the 142×12 axle fitting. All over the frame there are well sized hex bolt fittings and big spannerable pivots. So far it seems to warrant the lifetime warranty!
The Atlas is a brilliantly capable trail bike, very quick handling for a 110mm travel 29er and stable in the air/ on rough stuff. If these characteristics translate into the larger bike, I imagine the Spartan is Awesome.