My pick for favorite Top Coat is Seche Vite Dry Fast Top Coat. I first heard about it on youtube and on several blogs (sorry don't remember where) and decided to get it. I love this stuff!! It actually really dries quick. I use the top coat on one hand and by the time I'm polishing the 2nd hand the first one has already dried. Not only do I like that it dries fast but Seche Vite also leaves your nails super shiny. I also find that when I use really gritty glitter polish, this top coat makes my nails really smooth.
I can't even tell you how many bottles I've gone through. I'm even contemplating on buying a huge bottle, and that's just to refill my small bottle lol. Now I'm not sure where else this is sold but I bought mine at Sally's Beauty supply store. It retails for $7.99 but if you have the beauty club card you can get it for $6.49. I know its a little pricey but it's well worth the money. I would recommend getting e-mail notifications from Sally's because that's I how I bought it in the past for less. If you've tried Seche Vite before and have found something like it for less...let us know.
So other than these two, is there a top coat that you just can't live without? If so comment and let us know!