They certainly provide better protection. They also make it thicker. It really comes down to whether the added bulk and annoyance in your pockets is worth the added protection.
The only ones I think are worthwhile fully encapsulate the phone. Such as a Lifeproof Fre. Cases which aren't fully sealed allow grit in between the phone and case. Which can stick their and scratch your device. If there isn't a raised bumper around the screen perimeter. It won't be well protected either.
Once I switched to a larger phone. I found a case added too much bulk to an already large device. So, I'm going case free. It's a risk but it's a cheap phone. If it was a new iPhone I'd live with the bulky case to better protect it.