hey there, i was banded by dr. spivak 5-23-08 and well, as i'm sure you know, he's the best. but i will say this, this "no down time" is totally overestimated. i didn't leave the house for 3 days. be sure to have the pain meds & gasX ready before you get home. drink plenty of water and walk and you'll do fine, but unless you can wear loose clothes and bring a pillow, i would say--don't get your hopes up. it took me about a week till i started feeling up to myself.
also you will be totally fine for the trip! you will still be on mushies and you won't be able to lift anything over 10 lbs (i think), but you will feel totally great by then. i have read one thing about flying for bandsters, that the band has a tightening sensation when you're in the air, but it goes away when you get back on the ground. i think it's in that manual you got at the seminar. interesting.
now, as far as how much you lose in so much time--i do not know--everyone is different as far as that goes. i lost 10lbs the first week and dropping 2-3 lbs every 5 days or so, so far. who knows after the first fill and i am not being a stickler on fat free, sugar free. but i have been following everything else.
hopefully this helps.
hope everything goes great for ya!! i'm sure it will, keep us posted.