In my opinion, you have to be VERY careful with annuities. First, some have very high fees built in. Second, if a broker is involved, they take a cut. Third, the figure of 6% or 7% (I have even heard of 8%) could be misleading; it almost certainly is not an interest rate, but includes the return of your principal. For example, if you buy a $100,000 annuity at an advanced age, perhaps you get $6,000 (6%) back the first year. Only a small part of that is interest; most of it is a return of part of the $100,000 you gave them. They are using actuarial tables to compute how much, on average, they will have to give back, and it always is less than you paid. You are gambling that you will live enough longer than the average person your age to overcome the fees and profit that the annuity company takes.
Finally, the payments to you are often fixed amounts each month, unless you buy a variable annuity which has other risks, and so there is generally no adjustment for inflation.
All that said, if you go with a company with low fees and a very good reputation and a very strong balance sheet (so that you don't have to worry too much about default), the big advantage of annuities is that you don't outlive them.
Good luck, Lon