I know that are a lot of things involved in this(type of website, niche, posittion of the banner, colors, etc). But be i am interested for a general estimation for Technology niche. I want to use BuySellAds services with CPM advertise. Do you know for example what would be my CTR for putting my banner on top of any website there in a leaderboard banner? I need a real estimation from a real person who experienced what i want to experience with them.