Had a look at the Zurich Calculator. Splitting 50/50 between an Annuity and a ARF might be worth looking at. Also, a flat rate Annuity is better value up to age 89, from that age onwards an indexed Annuity with 2% annual increase becomes a better performer. So, how long do you think you will live, and would you prefer a bit more cash when younger? Assuming an Irish OAP for oneself plus wife, plus a ARF, plus an Annuity, one can afford to select the higher risk / higher reward ARF investment strategy.
Something else; if considering retiring to France, according to the current DTA, the Annuity and Irish State OAP are Taxed in France, but the ARF is considered to be a "post retirement investment" and not a pension, and is always Taxed in Ireland. An ARF investment of €720,000 paying 5% or €36,000 per year would be completely Tax free in Ireland, assuming a married couple. Then there's the French Income Tax on the rest, but at a much lower rate than in Ireland. In France the Social Charges (PRSI) are greater than the Income Tax, the split could be about 60/40 Social Charges/Income Tax. When you present an Irish S1 form to the local French taxman, no Social Charges are payable in France (or any other EU country), and in Ireland, PRSI stops at age 66 years when State OAP entitlement starts.
I have not yet figured out if the French include an Irish ARF which is taxed in Ireland, in their calculation, does anyone know about that?