I even bought a 2nd bottle, but also with this same problem: It always arise many small bubbles that make even the most perfectly painted nails look ugly. Whether the top coat is applied thick or thin, and also do not care if it is previously strong, little or not shaken, always the same result. Of course, it dries quickly, but that there are also in products from other companies.
The broad brush the top coat can be applied well. In normal use (office work, shopping, a little housework) he holds 3-4 days usually. If the bottle is half empty, the paint, as well as other, so thick that you can dispose of the rest.
I would not buy the top coat, I opted again for one of Essie.