Air bearings require a fairly tight tolerance as to the design of the tube for the entire run no? So I don't think it's a given magnets could be more costly if

Air bearings require a fairly tight tolerance as to the design of the tube for the entire run no? So I don't think it's a given magnets could be more costly if it means you use more expensive track materials but not a high precision construction. Any with air bearings or magnets both being a passive track on-going costs might favor the one geological events disrupt less.