Not likely in my opinion, Burberry will only have sale around July/August. Their items have been going so fast on the website that sometimes by the time I decide to buy something I really love it is gone. We only have one store in Hungary and say from shoes they only get one of each size and clothes too most the time so if I am in love with something I put it on hold till I can go in and buy it at full price. I do think it is worth it when something is unique and you love it, better than buying something you do not love on sale.
Now, no clue whether Saks and other online retailers that carry Burberry are likely to have a sale before July but they also have limited selections. I would suggest that if you really love something and it is not something they have tons of, get it.
Trenches they tend to always have but out of their classics less things go on sale too. I am not sure if Burberry is more expensive anywhere because stores are supposed to have the same prices worldwide and the site is also worldwide now so prices are the same or approximately the same in stores (depending on exchange rates too) but I mean Burberry stores and not dept. stores that may carry certain items. Shipping is also free so if you try something on and it is overpriced where you live just get it online from the official online store.