I just received my SUPCASE that the OP discussed in the initial post. At a hair under $22 delivered on Amazon, I am very impressed. It took 12 days from order to delivery, which was a bit worrisome since I was concerned about going "naked" for too long with my new device. But the seller emailed me to advise that the case was backordered, so I just had to be extra careful during my wait.
The case is very sturdy, and while it adds some bulk, it doesn't bother me. Coming from an iPhone 5, the phone already feels big in my hand, so adding a little bulk to it isn't a negative in any way, IMHO. The "flaps" that cover the headphone jack, the power plug and the s pen fit snuggly (is that even a word?), and frankly they add a good bit of protection I would think. It's not rated as waterproof, obviously, but the flaps give me some piece of mind for when I'm running with the phone or I happen to get caught in the rain while I've got the phone with me.
The cover does not feel slippery, but I wouldn't say the plastic is tacky or grippy either. The edges have more grip than the back, and they have slightly raised cerraded edges that assist with handling. It certainly is more confidence-inspiring than while holding the smooth edges of the naked phone.
The built-in screen protector is literally invisible, and I've noticed no degredation in touch sensitivity. And I do like the added protection it adds since I use the s pen and had concerns regarding whether the plastic tip could effect the screen over time. How much protection it would actually add in a drop scenario remains unknown, though I hope to never put it to the test.
As far as the holster, I don't know how often I'll actually use it. But it too is well-made and appears to be sturdy. The clip is solid and, with some effort, can be turned to allow for placement lengthwise or widthwise. The phone fits securely in the holster and I'd have no apprehension about it falling out accidentally.
All in all, I'm very satisfied with the SUPCASE. Eventually I would like to get a waterproof case (Seidio, Otterbox or Lifeproof if they they come out with one), but those aren't available yet AND they won't be $16.99 plus shipping when they become available.
I give the SUPCASE 2 thumbs up!