I have a spigen glas.tr slim. I had the original glas.tr on my iphone but had to swap out my device and get a new protector. Seemed like my oleophobic coating wore off my original one after 5-6 months. No scratches though and it stayed put.
With my glas.tr slim I put a tech21 case on it that night and when I used my volume buttons for music I noticed an air bubble. A piece of lint was left on the screen before installation right between the two volume buttons, and the case pressing on the screen caused it to get bigger. I just held the screen protector down for 30 seconds and it went back to normal. I shaved down the case between the volume buttons so it doesnt press against the protector where the lint is. Besides all this, glas.tr is awesome. Doesnt really matter if you get the slim or regular. No scratches and holds up extremely well. I will not be going back to zagg / ghost armour. Those 'work' for a little while then need to be replaced. With the glas.tr you dont even notice its on and doesnt impede touch screen at all.