I got the Nikon P900 while on holiday in Australia. Having had Nikon Coolpix cameras in the past I felt comfortable with it almost straight away.
You can have several personal programme modes on it, for immediate use. For instance I put the Birdwatching mode, continuous (takes 7 pictures while you hold the shutter down) onto Scene (the little wheel on the top) I use this one most of the time. That wheel also has automatic programme modes for Landscape, night landscape and night portrait. The wheel also has Manual and Aperture settings. Aperture I have the settings I was advised to use for macro images. You can also adjust the EV, for instance if you're taking a picture with a bird up on a telegraph wire, or top of the tree and is back-lit. That is all I can understand with settings.
There's also a video mode, but I've not worked out how to edit them, so haven't used it yet (except by accidentally hitting that button).
I don't find it takes long to start up, however, I've never used a 'proper' camera. It seems faster than any other camera I've used (all super zooms). I#m in the habit of pressing the On/Off button as I lift the camera, so it's ready to use by the time I'm looking through the view finder.
Flight shots can be difficult, but what I do if the bird is high in the sky, is to find a distant tree (or something else solid) focus on that then switch to the bird in the sky. But if doing this don't zoom in too much, or the bird will be hard to find. I've sometimes wondered if putting the camera into Landscape Mode would help, but haven't tried it!
You can see results from this camera in my Gallery
Media added by delia todd I'm pleased with them. With previous cameras I've always struggled to get pictures of a Treecreeper; I've managed a few since getting this camera.
Having said all that, I'm a birder who likes to take pictures of my day out, or to make a record of what's on my patches (my garden feeders, and a few other feeding stations I visit regularly). So I really can't compare the 'quality' of pictures taken with a DSLR, which I couldn't afford, nor carry. I couldn't be bothered taking all the lenses for the range I want to take... 5-20 feet, close-up (macro) and landscapes!
The P900 has been superseded by the P950 and P1000. If you can afford the latest one, I'm sure you'll be happy with it, otherwise you should be able to get the other two second hand or maybe old stock at a much cheaper price.
I can feel some members wincing at my lack of correct terminology LOL