Ergo M575 Wireless Trackball (Black)

So I will start this review by stating that I ordered this trackball by mistake when searching for the old MX Ergo in a rush, picking a 3rd part seller (usually a mistake as well) and ending up with this monstrosity.I have been using the Logitech trackball from the M570 which I several, but they all had the same issue with poor micro switches on the mouse button, I upgraded to the MX Ergo 5 years ago and its still going strong.I needed an extra trackball and wanted the same MX Ergo, which has been retires but I thought I had found old stock, I must have miss read and I have this Ergo 575.Where do I start, well its flat, this means that your hand and wrist are at an uncomfortable angle, and not gaining the benefits as much as they should for using a trackball. But worst still is the fact that its made is a silk finish which is just slippery and I find myself constantly having to re-adjust my hand. Again, this looses ALL the benefits of using a trackball.The final issue of this "Budget" version, which is still over £40 is that it is not rechargeable or has the ability to connect to two machines.Considering you can get the latest MX Ergo for £80 this is simply a waste of money.I am kicking myself, had this been purchased from Amazon I could simply have returned it and purchased the correct one, but because of these dreaded 3rd part sellers I am now stuck with this useless lump of plastic and will be spending a further £80.I guess at least my cat will like chasing the ball around the room and I have 1/2 the batteries I need to replace the ones in my remove when they go flat!