Corsair has a reputation for high quality power supplies. They consistently earn high marks in technical reviews. They are stable, reliable, and come with a 5 year warranty. The brand new models come with a 7 year warranty.
Antec was not initially known for high quality power supplies. The have tried to improve the quality of their power supplies and in some cases have been successful. It just depends on the particular series. For example, the newer Antec Earthwatt power supplies are very good and certainly an improvement over the old Basiq power supplies which were low budget units.