These plants sure have a great sentimental value Andy. I have one vinicoloured raff that has been with me ever since I started growing Nepenthes, now it's close to 8 years. Day in day out you water the plant and watch it grow and pitcher.
Your ridleyii and holtumii are crazy beautiful specimens I must say. Your bifurcatum, you can start dividing the babies and grow them separately. Or you can shift it to another tree which can support its bulk better. Is it hanging on a small tree trunk? It looks alarmingly heavy...