thats why I was hoping to hear about people's real experience.
It depends on what is important to you.
Here's what I have posted to htis question before...
I would be reluctant to reschedule. I have read about a thousand posts here over the past month and rescheduled ones are often asking how much longer they should wait before inquiring where they are at in the system.
So, if I were you, I would postpone the trip until after the Oath date or postpone the filing until after the trip.
The USCIS is a huge system and big wheels turn slowly. Stepping outside their schedule system may cause more delays.
I am guessing, but when it is your turn for say the FP appointment, your name just goes on the bottom of that list. When you reschedule, someone has to find a rescheduled open slot to slide you in for the date you requested.
Also there may be a bunch of people that have asked to reschedule and you may in the middle of that list somewhere. Get the drift? You are likely to compound the delays but ultimately up to you.
My suggestion is to go with the flow.
As anire-take suggests, figure out what is important. I have to allow 6 hours to drive each way and if I get an appointment before 10:00am I have to stay in a motel the night before which I can ill-afford. BUT NOTHING is more important to me than becoming a Citizen.