I finally got up to Vegas and had two dinners at Lotus of Siam (I was only in town for two nights, so that's the best I could do). I want to thank Dave Feldman and all the other hounds who've posted here--those postings helped me order some amazing things. Also, having mentioned that I'd read about L.O.S. on the internet, Bill and his staff treated us like we were either old friends or new restaurant reviewers for a national magazine. Their advice and suggestions were excellent and helpful. They even brought us tastes of two different rieslings, so we could decide which to order. All the food, with the exception of the wrapped fried banana, was excellent and interesting. In fact, I can think of only 2-3 dishes I've had in other Thai restaurants that would match up to the general quality of everything at Lotus. We ordered things moderate to hot (5-7) and I wouldn't have minded even hotter, but I am very tolerant of chilies. I hate to repeat what others have already posted, but I do want to briefly mention our favorites, hoping perhaps to be helpful to other L.O.S. neophytes.
1). The barbecued catfish is the best Asian whole fish dish I have ever eaten. The succulent, moist fish matched perfectly the smokey charred skin. The catfish in the garden (deep-fried and served with julienned green veggies and sauce) was also good, but the barbecued version was, imho, better
2). The fried rice and sour sausage appetizer was incredible--layer upon layer of flavors. It was so good that I was picking individual rice grains up off the platter after we'd eaten the rest.
3). The giant Thai prawns were as huge and rich as other posters have described them.
4). The northern pork stew was a perfect compliment to the catfish. Extremely tasty and tender with complex garlic and dried chili flavors.
Anyway, I just want to again thank Dave and the rest of you who have posted about the restaurant. An experience like this makes me want to rush over to the chowhound store and spend money to help support this wonderful site.