Seche Vite Fast Drying Top Coat is by far the best top coat I've used. For years I was an OPI devotee, and I assumed it was best if I used OPI topcoat with their polish. Seche Vite, however, has provided a much clearer and glossier finish than any other top coat I've tried. Also, it does not nick once it gets dry.
People tell me my nails look great all the time and they think they look professionally done. I think this is largely because of the glossy and clear finish I get from Seche Vite--though I will take credit for the years of experience, but a manicure or pedicure won't look professional no matter how good you are if you don't have a good top coat.
I've noticed that if I use and older bottle of Seche Top coat that I'll be more prone to cracking of the top coat, but that's only if I happen to pick up a bottle that is over a year old. Just be sure to keep a fresh bottle on hand and close it tightly, and this should help extend the life of your top coat.
As far as the one reviewer who complained of chips, perhaps the bottle of top coat she used was an old one. I'm not sure, but I do my own nails every week and don't have any problems with chipping (unless I'm doing hardcore work, in which case ANY polish would chip). If you're tough on your nails you may want to also use "chip skip," which is an OPI product.
One final note, as top coats do, this one does tend to absorb some of your nail color. For instance red polish might tint your bottle of top coat a light red. If you don't always use the same color of polish, I'd recommend cleaning your applicator brush after using the top coat (with polish remover). Otherwise, next time you go to do a french manicure it might have swirls of red in it.