I own the Trident Case, and I have no issues with the screen cover not matching 100%.
There may be a slight gap between the screen cover and the phone itself, but it is minuscule at worst. I have yet to have an issue with the touchscreen not working because of this 'gap'.
The case is pretty sturdy overall, the only real gripe I have against it is the plastic cover over the rear-facing camera reflects a fair amount of flash, distorting pictures. I had to remove it to take a decent picture.
Hope this helps.