The AFP-512 has a LOT of issues, from the extruder frequently clogging, the bed being impossible to level due to warping, and the electrical connectors on the hotend degrading. The design of the bed leveling is also poor, only having three knobs instead of four (by design), each of which changes the tilt of the bed along multiple axes, making it very difficult to get the whole print surface level. This has led to this printer being down more than up.
The monoprice 3d printers that we have currently seem to be heavily used and have issues less frequently. The Monoprice MP10 is $300, and features a build surface that is the same size as the AFP-512. Most appealingly, though, it has an assisted bed leveling feature, which should help limit the number of times that printer beds need to be adjusted and also improve the ease of getting a bed to be properly level -- Hopefully translating into less downtime. It should work with existing OctoPi systems and uses the same diameter filament as the other 3d printers that we currently have.