In my experience, it's very hit or miss. Everything is very well stocked, but sometimes things aren't the biggest bargains, and other times it's like amazing how cheap things are.
It is very hit or miss. Some stores are great some days and other days the stores are just so-so. As a whole, it's definitely worth a trip. I have bought some really nice things from there, or rather my parents used to buy me nice things there when I was growing up. IMO they tend to go all-out on sales so it's best to hit the place at a time like 12 am on Black Friday and shop through the night.
My mom scored a pair of lizard Gucci pointy-toe flats for $198 in 1991. I wish my feet were small enough to fit into them because they would've been MINE.
I agree with what the others said-- it can be hit or miss but is always worth the trip. Also, some of the outlets are MUCH better than others. Some have really great stuff while others basically just stock really out of style or damaged stuff.
At the very least, if I don't luck out at the designer outlets, there are places like the Banana Republic outlet that always have great deals on basics.
I also agree worth the trip. There are a huge number of stores! The designer outlets like Gucci, Chanel, Prada can be hit or miss but I agree with uesgirl you can usually find some good deals at Banana at the least. The Department store outlets always seem like so much work to search for something. I did get a great deal on cashmere cardigans at the Saks outlet last time.
Balck Friday, I was not aware...I'll have to sign-up for their newsletter so I can find out about things like that!
The stores are hit or miss, but I usually find great deals. However, I go there a lot b/c I am only 20 minutes away. Also before you go sign up to be a VIP member (its free), then print out the coupon for their coupon book. Some of the coupons aren't worth it but I find use for them sometimes and most stores have a coupon in the book!
I've only been once but I'd say it's worth it - I'm thinking of making another trip myself. If you're looking for something specific that would be much cheaper in an outlet than in a regular store - say a suit or a formal dress - you'll probably find some great deals. I remember seeing a gorgeous Theory suit when I went but alas, even on sale it was still a little above my budget...
Also try and visit on a day when the weather's nice. You have to walk outside to get between the stores and it sucks if it's raining/snowing/frigid!
ETA: Have any of you taken the bus up there? Is it a pain or just about as good as driving?