What's the best aftermarket reversing camera?

I am considering fitting a reversing camera to my recently purchased Honda Jazz, to supplement the reversing sensors. I am looking at the Halfords EchoMaster monitor and reversing camera, but the reviews...

Can you recommend a tyre inflator/jump starter?

Please can you recommend a tyre inflator/jump starter? I have read about many of these but there seem to be a lot of negative comments

Can you recommend a car polish to protect the paint on my new car?

I have just purchased a Subaru XV. I was offered body protection at a ridiculous cost. Can you recommend a polish to carry out the protection myself?

What dashcam should I buy?

Following a minor collision in which the other driver accepted full liability has made me realise that I was lucky, especially when there were no witnesses. I have decided to invest in a dashcam. Any recommendations?