I just bought a bunch of old Matchbox kits (5 for $20 CAD) at a local swap meet. Some of the Matchbox kits have been recently re-poped as Revell kits. I built a bunch of the dual and tri-colour kits as a kid, so they are a bit of a nostalgia build. I would love to get my hands on a 1:72 Matchbox CF-104.
Like Scott mentioned, they are not up to modern standards, panel lines are wide and soft, but that aside they can be a fun low stress build, if you're not AMS stressing. My main worry is the decals, in the kits I got they are very old (30 years-ish)...
Jason