I haven't any experience of Orange but my son has had it for almost 12 months. He was telling me at the weekend that he cannot wait to change to another ISP. Basically he has a lot of connection problems and he said that Tech Support was useless and that's when they can get to talk to them or even understand them.
Like Wendy, I'm with BT, on Option 3. It's a little dearer than the norm but I've been with them since I got rid of Screaming Net (how many remember them) and rarely do they go down. Also they have the best connection speed for my area compared to the likes of Talk Talk, Sky, Virgin, Tiscali etc.
MacAfee suite, which comes with the BT package is excellent, apart from it's Site Advisor which causes I.E. to freeze. Easy to remedy though by disabling it in Tools>Manage Add Ons.
If you do change be aware that some ISPs aren't too keen on giving out MACs despite it being law. Also I read of lots who continue getting charged after leaving, Tiscali being one of the worse. Tiscali took over Screaming Net and I had the same problem all those years ago so it seems things haven't changed.