Door Security Bar Breaks Too Easily

We have two sliding glass doors in the back of our house.  they both have locks, but I like the feeling of extra security.  We bought two of these dual function door security bars so that I felt safe when my husband was not home.

The bars are amazingly flimsy. While they were easy to install, it did not stay in place.  About a month after screwing it into the wall it fell out.  It turns out the screws that come with this product were rather short and did not hold it in place.

The second problem we had with these bars, and the reason we stopped using them, is because the little clip that is supposed to keep the bar locked, does not stay locked.  The bar just collapses without the clip. 

The bar was rather affordable and I guess you get what you pay for, but I would have thought that a company such as master lock would have made a security bar that would have kept our family a little more secure.