I would say it's generally better to take RMDs early in the year rather than late in the year, but if you do so you won't be able to use annualization of income to reduce any underpayment penalty. Instead you'll need to pay estimated taxes equally for each of the first three tax quarters based on 100% (or 110% for those with higher AGI) of the previous year's tax liability or 90% of the current-year projected tax liability, then possibly adjusting the Q4 estimated tax payment if necessary to avoid overpayment or underpayment.
