Depends on your desires and budget
For myself, I'm only going to invest in platinum rated, modular power supplies that are tried and true. The top rated PSU's of this nature frequently go on sale for $100-$110.
If I were to make a purchase today, I'd grab the Corsair AX760 from Newegg. It's currently $120 after $20 rebate (if you don't mind dealing with rebates.), arguably best in class, and, most of all, features a 7 year warranty.