What's the opposite of 'wonderful' I wonder

 What walks down stairs, alone or in pairs and makes a slinkity sound?
A spring, a spring, a marvelous thing!
Everyone knows it's Slinky.

It's Slinky, it's Slinky, It's fun, it's a wonderful toy.
It's Slinky, it's Slinky, it's fun, It's a wonderful toy.
It's fun for a girl or a boy.

For those of you, like me, whose formative years were the early 1960's, you probably had, at some point, a Slinky. I'm sure the only reason I wanted one was due to the television commercial with the clever jingle noted above. I hope your experience was better than mine, although I doubt it could have been.

The commercial I recall showed at least a couple Slinkys in a lively march down a long staircase. I grew up in a modest single-level ranch house where the only thing approaching stairs was the single step between the kitchen door and the garage floor. Later, when my parents had added on a Family Room in the back of the house, there was a similar single step down to the patio. So the jingle's premise fell apart quickly. What walks down stair? 

So the number of things this "wonderful toy" could do were limited. You could place each end in your outstretched hands and raise and lower them in a see-saw motion. That was good entertainment for ten to fifteen seconds and actually did result in a "slinkity sound." Or, you could stretch it out to see just how long you could make the thing. This required the assistance of a friend, I should say a TRUSTED friend. And then one of three things was going to happen: this marvelous spring would be stretched so far that it would never go back to it's original coil, your trusted friend wasn't really trustworthy and you got a face full of metal springy recoil, or, more likely, the spring would twist a bit in the middle creating a stress point and then break resulting in a piece of what I'm convinced they use for razor wire screaming back into the bodies or face of you and your now former friend at the speed of light.

Why did I ever want one of those things? More importantly, why did I think it would be a good idea to get one for my kids ... even if they were plastic now. Broken jagged spring is just as deadly if it's plastic as it is when it's rolled steel.

Fun for a girl or a boy, or lucrative for emergency room staff? I don't know. Now, where did I put my old chemistry set?