It starts really well, especially the experiment footage was really funny. but it goes bad after that, with a predictable generic ending.

Unless you're a completionist, you can feel perfectly justified in skipping this train wreck. If you want the funny parts, watch the scenes of him being tested in the lab. His dialog is at least enjoyable and somewhat witty there, but then you've done your ALF'n duty and can try to forget this even exists.