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The outlets do have sales, I don't ever remember ours having a storewide sale, it's usually one line or something or spend this much and get something free. But I'm also not there every week.
The stuff in the outlets is of various quality. Some of it is not as good as retail, some ie exactly the same stuff, just discontinued or whatever. Some if retail stuff at full price. If you ask, they will tell you which it is.
You need to also check on the warranty from the outlets. Depending on what you buy, there may not be any. Or there may be a full warranty.
Stores will have sales, they are usually mentioned here, so do a search for Tumi sale and you will probably find the past threads. They come at certain times of the year and are probably pretty predictable as to what they will have on sale or what the savings will be.
Saving $100 or $200 is nothing to sneeze at, All but one Tumi bag in the house is from a local outlet, and we have never had a problem. If it wasn't for the outlet, it would probably be just that one bag, we never would have paid full price for the others.