The No Brainer Annuity or 4% from Investments Which Is Better.

Annuity Option: 
From http://www.immediateannuities.com/  if you want a cash stream of $3000/month you would need to $677,000 to purchase that security.    Risk is low assuming inflation does not go crazy and the company selling the annuity does not go bankrupt.   Additionally, you would have to read the fine print...

Investment Option:
A better alternative might be to get 7% investment return on your money in a 3% inflationary environment, you would get $2256.67 per month on a $677,000 dollar investment.    The main risk here is that you would have to earn 4% better than the inflation rate and your investments may have larger risks.   A huge benefit of this option is your principal is never effected.    That offers you an emergency fund or travel fund.