Had a go at cleaning my engine bay today and I must say it turned out well!!
I used GUNK degreaser and Meguiars engine cleaner and agitated with a paintbrush and rinsed lightly with water. I then used Fenwicks cleaner and sprayed everywhere then wiped with a microfiber cloth. I did my usual trick of applying wd40 to moving components to provide some lubrication and extra protection against the elements.
Once rinsed I started the car to allow the heat to dry the majority of the components. I gave the plastics a rince and a clean with wash and wax and used Meguiars plastic protector to give a nice sheen. Took me about a hour and im well impressed with the results.