My husband had open RP on the advice of the surgeon - the uro is (or at least was then) considered one of the top PCa specialists in this country and one of the first to do keyhole RP but he advised that in J's case he would get better results by getting his hands in and feeling, particularly in relation to sparing some nerves.
It is not necessarily the case that ED will be more likely with open RP. In fact, statistically, the last time BAUS published the data, it was still the case that open RP had slightly better outcomes in terms of continence, erectile function and recurrence although LRP was better on blood loss and time in hospital. Open RP often means less time on the operating table as well. Unfortunately, BAUS has stopped publishing the annual stats so we will never know when the balance tips from one method to the other.
In terms of the op, J was in hospital for 4 days I think and yes, it takes longer to recover. I see lots of hospitals now state in their patient info leaflets that a man having LRP will need 6-8 weeks off work - generally speaking, a man having open RP will need 10-12 weeks to recover fully. Might need a little longer before he can drive safely as well.
If you have time, buy him some soft track pants with a drawstring & elastic waist in a dark colour and pants (not boxer shorts) one size bigger than usual - M&S do some track bottoms which are tumble-dryable. J had to sleep on his back for the first couple of weeks which he found difficult - looking back, I wonder if one of those pregnancy pillows might have helped.
Lots of books, crosswords, whatever to stop the boredom. They say that you use up 5000KCal per day recovering from abdominal surgery so he will feel exhausted doing nothing!