I've been to the one in San Marcos many, many times. It's a hit or miss venture.
The adult clothing selections are limited to mostly extra small or XXL+ sizes.
There are usually a lot of bed and bath items, seasonal items (Christmas, Halloween, Valentine's Day) and occasionally there are BIG discounts on discontinued watches. My DH and I bought two sets of Steamboat Willie matching watches for $50/set, originally priced at $250 a couple of years ago. My DH collects Mickey watches, so he calls the Catalog Outlet every now and then to inquire.
Sometimes they have "returned" items from the catalog that have been personalized, and unless your kid's name just happens to be Guinevere or Poindexter, those items are useless.
I have, however, bought great kids' clothing there that I have never seen in the catalogs or in the parks, so sometimes it is really worth the trip. Two years ago we did all our Christmas shopping for toys and clothing there during the summer and got great bargains on good stuff.
We go about twice a year (in-laws live in San Antonio, about 35-40 minutes from San Marcos) for a Disney discount fix. We used to get postcards from the store to let us know when special sales were going on, but it has been over a year since we last received one and before The Disney Club cards were available, there was a Catalog Outlet Discount club card that gave us 10% off sale prices.