= job done in less than three hours, my record is 1.5 but I was totally fooked afterwards 
Great advice. How the hell did you manage all that in 1.5 hrs. You must be a human dynamo

Well put. I was going to ask the same question. Would you recommend sealing, or using a glaze perhaps, and applying with a DA? Or go easy by hand?
Glazes tend to have 'filler' properties which can help to disguise some fine scratches/swirls. They will also enhance gloss, but don't really offer much in the way of protection.
Sealant gives good protection and adding wax on top gives greater depth to the shine or gloss. Sealant on it's own can give quite a sterile/clinical shine. I would always top sealant off with wax as Ginge advised.
Sealant can be applied by DA, but best done by hand imo. Let it cure for about half hour then buff off by hand using microfibres. Avoid getting on trim as it can stain.