It really comes down to your appetite for risk. I strongly agree with Foxy. If you have a government or index linked final salary pension I would be most reluctant to transfer it into QROPS. Markets can crash and drastically reduce income, despite the most conservative portfolio structure. A government pension is about as risk free, fee free and guaranteed as you will ever get and it is a lot to give up.
You also talk about the consequences of a 50% cut in pension if you die soon. But supposing you and your wife live to 95 and the QROPS dries up in your 80s - as it is designed to do. Where would you and your wife be then.
If you haven't already done so, have a look at the GAD rates for male/female v age and it will paint a pretty picture into your 70s and will then get progressively worse and worse. Once you reach the actuarially determined age of death your QROPS will be completely drawn down and provide no income whatsoever - which is rather inconvemient if you are still alive.