The Harbor freight test stand is cheap and folds. Like someone said, you'll need to replace the top boards after a while. I put a plywood shelf under mine, not permanently attached, just 4 wood screws underneath screwed in part way. The shelf can be placed on the bottom fame and the screws keep it from sliding off. A photo shows my Pegasus 2.4 idling on the stand with a disc brake rotor on the shelf. Yes, the Pegasus will tip and travel it on full throttle!
MECA member Jim Hawk demos a lot of engines and has them premounted so he can quickly install or remove them from his Harbor freight stand. I came up with another quick mount system. One of the bases uses an Edson (available from MECOA) adjustable mount I've used for engines I break in or test, where I don't need a permanent mount.