All, I'm trying to determine the interior differences before and after the mid-cycle refresh on the GS. The 2017 I recently looked at had a lot more soft touch leather, especially on the dash than what I remembered being on the 2014 and 2015 cars I drove two years ago.

If anyone can provide details and maybe some comparison pictures I would appreciate it.

 

One good way to do this is to go to the Lexus site and look at the brochures for the older year Certified cars. That should give you all you need to know from the source. Good luck!

 

I have had exposure to both interiors for extended period since I've had a 2013 and 2015 in the past, and currently drove a 2017 GS350 F-sport.
The most significant change I noticed are the obvious: new (seems more substantial) aluminum trim, new gauge cluster (now LCD), additional Enter and Back buttons on Remote Touch Interface, new frameless rear view mirror, improved Homelink system (allows for short press rather than holding the button down), and Customize mode now available for drive mode selector. The adaptive cruise control is standard for 2017 and functions at all speeds (can be used in traffic jams), and works well with the Lane Keep Assist.

Some subtle changes I noticed: new (seems more substantial) interior door handles that feel less plasticky and feel more like metal, new seat stitching that make the seats look more attractive, new gear **** (now bigger and with aluminum trim), new (more attractive) steering wheel which feels to be better quality, and new keyfob plastic (smooth now rather than textured; doesn't matter if you put the leather key glove).

You mentioned noticing "more soft touch leather, especially on the dash," but actually it's the same. One thing that the 2015 had which is better than the 2017 is the door pockets were lined at the bottom with a soft material so that things wouldn't rattle when placed inside; they removed them on the 2017. I purchased some rubber mats that were cut to fit to line the bottom.

 

I agree on the steering wheel improvement. The Naguri aluminum looks better too and obviously the front end. Too bad you have to run a plate in most states.