Use the longer life one, the ripple current rating will only add a small amount of extra heat if you run at full rated current, but the longer life one will last longer, if it runs around the same temperature, and with a current well under the max rated ripple. Derate for lower operation temperature and the 5000 hours extra will be well ahead of the other, as each 10C drop in operation temperature will offer more than double the rated life of the other, and thus if they run at a typical 75C the first will last 16000 hours, say 2 years, while the other will last 56000 hours, roughly 7 years, and this will increase for every lowering of operation temperature, say by not having a hot regulator cooking the capacitor, and having some airflow across the board.
As to voltage a modern capacitor is fine with lower voltage, your 25V capacitor will be fine with 3V3 applied, and will last just as long. modern branded capacitors with quality pure aluminium foils do not degrade as badly as no name unknown impurity foil types, or very old ones with very old foil, made before QC got to the point they could remove down to the PPM level in the manufacturing.