The "best rate" depends on your situation.  If you plan to buy a home and move in 2 or 3 years, you may be better off not paying points since it could take many years to recoup your cash outlay for points at closing depending upon current interest rates. If you anticipate rates to rise in the future or if you do not intend on moving soon, then it may be wise to "buy down" by paying discount points.  

When comparing loan products offered by different lenders, be sure to compare "like" products (exp. 30 year, fixed rate loan with 1 origination fee, no points) and obtain quotes at approximately the same time. Comparative pricing should also be based upon the same period of "lock-in" since products offering a longer "lock-in" usually carry a slightly higher interest rate or fee due to the greater risk of uncertain future events.   Ask your lender to present several options for review before making a decision.