The Outer Limits is always entertaining and if you enjoy the series you should enjoy this episode. Having said that, this is one of those average episodes, that is definitely not a must see. It's a bit slow, the monster is not very intimidating and there's really no "wow factor" in the climax.
But as I said I was entertained. The actor who plays the "investor" is Renault from Casablanca. It took me a second to key in on that. And one of the things thats fantastic about old television is that it is in some ways a time capsule of our culture. It was fascinating to see how the husband and wife interacted. She implicitly supported her husband as she was his priority though most of it. I love when he gets out of the lab and she's waiting for him fully dressed up with a martini for him. They dress for dinner. They take a night off and go out dancing. It's interesting how the show shows us the fantasy of what life should be like from a 60's perspective. In 2012, dressing for dinner sounds bizarre. I think observing the main character's marriage was more interesting to me than the science fiction story.
If you're a fan, check it out. If you're trying to introduce someone to the series, avoid this episode.