I never used any of the two, if you are afraid that you can't sleep try the melatonin.May be 20 minutes after the OO.
For the first time may be I did not sleep well, but it was more because of the unknown. Now if I can't sleep I either get up, watch tv or read.
They suggest just the first 20 minues to be quiet. Then there is a flush where grandma walked the whole night. I think it is under cleanses. The stones come out, if you have any, in the first 20 minutes.
Just make sure you drink enough water up till 20 min before and 20 min after the ES (Andreas Moritz protocol), since a lot of people stop drinking after 2 pm got dehydrated and/or felt nauseous.