Owned many mice over the years and used even more on the job and school.  This is definitely in the top 5 in my opinion.  It is comfortable to use has good placement of buttons.  Scrolling is smooth, mouse pointer operations are pinpoint.  The rubberized grips are nice and much better than the plastic on cheaper mice.It unifies with other Logitech devices through a unified receiver perfectly.  The one thing to remember is if you are not using the included receiver, you'll need another pointing device until you can pair the MK510 with your existing unified receiver. 

Question: What do you think about grip?
Answer: The rubberized grips are nice and much better than the plastic on cheaper mice