I went to the Winter sale last year on the first day and yes, be prepared to wait a while to actually get in. The line wrapped around the whole of the back parking lot they have there; it's not a huge lot, but still, I think there must have been ~75 people ahead of me. They had quite a bit of Saint Louis crystal, however, a lot of it was just odd lots -- if you were looking for 4 or more matching items you'd be out of luck. Some Hermès plates in discontinued designs (Patchwork, Brazil) were also there. They also had a nice collection of small leather goods in lots of colors and leathers. Lots of ties (and lots of ties I'd paid full price for -- I keep trying to get myself to only buy ties at the sales as no one seems to like the colors I like, but I just cannot do it!). Lots of huge tote-like bags in leather and leather-canvas. 4-5 racks of men's rtw. A utility rack loaded with dress shirts. A big wall of shoe boxes, but for men there were not a great deal of varieties. 4 tupperware vats of previous seasons' scarves, and racks of women's rtw.
I also went to the very last day of the Summer sale there and I was still very happy with the selection. Not as much crystal or porcelain, some H wood boxes (but all with surface flaws that kept me from actually buying them as I know I'd not be able to overlook the defects), cadenas, enamels, lots of earrings, again lots of small leather goods, ties rtw and shoes. And despite the fact that the day I went they were having problem after problem with the cash registers, the SAs were so much friendlier on the last day, and I didn't have the feeling of a salmon swimming upstream when I decided to go ahead and get that small leather item I'd passed on but realized I wanted it right before checking out.
In short, I think any day you get there you'll most likely find a few items that you'll be happy to get for 40-60% off. I just know from now on I'll be content to go on one of the last days to avoid the crowds and the standing in line.