I wanted an affordable mouse for use in office when I work, went to All IT in Digital Mall PJ to take a look see. Was gonna get a Wireless Intellimouse Explorer since I figured the tilt wheel was good for work, but in the end, got the MX518 for RM109 instead.

So far, impressions are very good. Ergonomically, I think my MX1000 is much more comfortable. However, the DPI selector on the MX518 is more useful that I originally thought. It's good to be able to ratchet down to 400dpi to get better precision when doin Photoshop work. And I ended up programming the 2 side buttons as left and right scroll to replace the functionality of a tilt wheel.
All in all, very satisfied with it. The only complaint is that similar to my old MX700, the mouse doesn't sit flat, I can rock it side to side slightly so that's fairly annoying at first.