hardly. although i have seen sale of 3rd parties lens, some older models to clear stock.
comex is meant for people who thought that they can get a better variety to compare (which is too chaotic and there is a lack of informed decisions) and who thinks that a discount off the recommended retail price is a good buy. this group are often girls and the compact camera group. DSLR users tend to be buying more expensive equipment and usually do not rush into decisions, hence are usually not targetted in such fairs.
besides, you need to know the price first to compare.