First night using this cap to to replace other non-center pinch lens cap, I dropped the cap and the spring fell out. It was easy to reassemble together again, assuming I could find the spring (next time may not be so lucky). At further examination, it was held together fairly weakly. The plastic hooks are softer than toothpicks. Wiggle them too much, clips would come undone.
Are they worth $3.60? Maybe. It gets the job done.
broke the first time I put it in my camera bag :-(
This lens cap broke the first time I put it on a lens and slid it into my camera bag. One of the little pinch pieces popped off, and the spring flew off into oblivion. Now the thing is a useless chunk of black plastic that won't stay on a lens.
PROS: it's inexpensive, black, and resembles a lens cap