Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: Poor tracking, unacceptable wake-up time
Review: Logitech, so far, always appeared to me as being a first tier supplier of quality mice. I am shocked how Logitech could dare to release such a product. They are actually back to the good old days where users would need a mouse pad in order to get proper performance. The V400 does not work well on dark surfaces, it does not work well on light surfaces and it does not work well on tablecloth. I have actually bought the V400 because I did not like the scroll panel of the V500. To my surprise the V500 with conventional red LED works well on all mentioned surfaces where V400 is a nightmare. It is a darned cheek when Logitech claims to have introduced the V400 "... all terrain laser tracking technology".
