They all have very similar specs. The CPU models only differ by 100MHz and RAM ranges between 12GB to 16GB which is more than enough for games. I actually prefer matte screens since I do not like reflections.
The ASUS ROG G750JM-DS71 is definitely the chunkier of the lot, but it might have better cooling than the others. You need to read though the reviews to find out if there are any issues with overheating for all 3 laptops. The Acer looks the sleekest of all of 'em and it has a 128GB SSD; the other two laptops only have a hard drive.
Based on esthetics, I would chose the Acer, but the 128GB SSD is a nice feature as well for a laptop that is not that much more expensive compared to the others. The only reservation I have is that Acer laptops are generally only considered to be average quality laptops while Asus laptops generation are considered above average quality. However, I know Acer has been focusing on quality for their more expensive laptops in the recent past. It would be nice if the HDD was 7200RPM instead of only 5400RPM. However, you can always replace the 5400RPM HDD for a 7200RPM version later on or simply install another SSD.