Autoglym is a decent product, so maybe it doesn't like being applied when it is hot? I have found to easy to apply and remove and with all the fillers it contains, to be very forgiving.
I haven't used Meguire's from a bottle, only the carnauba wax in a tin and found it to give a slightly better result than the Autoglym - but these things are subjective and down to taste. I find a carnauba wax gives a greater depth to the paint, probably because it is slightly less shiny thus less reflective.
The Croftgate product is synthetic wax I believe, and I suspect it will give a very "hard" shine to the paint, rather than the "soft" glow from the carnauba which I like so much on my diamond blue car. It could look fabulous on a dark coloured car though; it does on j-r's amazing 4.0S.
I'm not knowledgeable on 'detailing'. I just thought I liked washing the car and only recently dicovered there is a word for it and a whole world out there!
