Feeding the aphids to Drosera is most likely no final solution, but might keep them down until spring arrives. Then beneficial insects push in and are likely able to solve the problem. If you have few plants and can observe them very often.
The main danger with aphids is the probability that they might spread some viral or other disease if this is present in your stock.
When I watched this excellent video from Willy I was tense, if it will give birth to some baby while being eaten by the Drosera.

They give quite early birth to babies, because they are usually parthenogenetic and even a baby might already be pregnant.
Therefore it is quite difficult to get rid of them without chemicals in the winter.