I've had several. Completely numb so no, under an hour if straightforward, prefer them to fillings. No worse than other dental treatment so cannot see why you would need day off afterwards.
It is a large job but you get sufficient painkillers that pain is minimal or non existent. But may need more added as the job goes on.
My memory of awful these days but I think I had it all sorted in an hour or two with a temporary "top" which was then replaced with a permanent one at the next visit.
No you will not need time off save for the dental visit itself.
In fairness I should point out that my dentist was suggesting I visit an expert at one stage but found he was able to do the job himself after all.