Videobegin wrote:YES but : when you buy used products, you can check if product is really like new
True, but the general condition and how well it's looked after is the better indicator. There's little to go wrong with the solid state electronics now unless they've been badly stored - often electronic faults will appear early, but you always have to check everything works.
I am always amazed at people selling gear on Ebay, who can't even be bothered to clean the item or supply a good photo of it. I bought a used Canon broadcast lens for little money - I cleaned and gave it good going over and I know I could have flipped it almost immediately for double the price.