For me it not took much time but a few minutes.
For some people it is a more security as they will be more secured from hackers while some people do not like it and for them it is a headache.
What is your opinion about that system in xapo?
Almost every platforms that does not let you own full control, have some elements of back end and controls put in place is just ensure some form of security. Even on Gmail when you send a mail, there is a time lag in before its finally sent and when you can either undo, or call back the mail which sometimes have been a life saver to a lot of embarrassing situations. It could be long for some people but the day you make a mistake in sending a transaction and you get the chance to quickly reach out to support to stop it from going through you will appreciate the effort and control especially if the amount involved is huge enough to cause financial embarrassment.
What I think they should do in other to improve is just like Electrum that allows you to tick for whether you want a transaction fee to be final or not, same can be applied to confirm if you want your transaction to go without timing difference or not.