Be careful what you wish for, Deninmem.
There've been any number of posts on here about what poor VFM an Overnight represents. You're actually paying someone to sleep next to you for some of the time; not to "sleep with you" for all the time you've booked. A number of girls who offer long [4-hrs] daytime appointments can be better WFM.
Additionally, if you're going to have an Overnight, you need to be sure that you get on with the WG you've booked; otherwise it could be a very lo-o-ong night, if you know what I mean. That's why people on here often advise against having an Overnight with someone who you've not met before.