I have been an owner of an M1 for a few months and there were several things/projects I wanted to do that I just could not do with the M1 without extra effort.  For example, engraving metal without preparing it ... being able to cut larger pieces ... So, I went back to XTool and bought an S1.  I now have a 10W S1 with the 2W Infrared module.  I had to share MY results, as I LOVE my IR module! These photos hopefully show the engraving effects of the 10W vs the 2W IR module - I personally think the difference is VERY noticeable and cool.  

The "test" file is not this actual graphic, since I purchased this file and cannot share it.  The original image is white on black, so I took it over to imag-r and converted it to Norton Black Acrylic, imported the image into XCS, and continued on. 

The left side of the dual photo was engraved with the 10W laser module.  The right side of the dual photo was engraved with the 2W IR module.