NiCads have and will continue to serve us for many many years. But as we keep adding more demand to our systems the need for more power output was only a matter of time. I have only had one real bad problem with NiCads and as luck would have it that was in the pits during a charge cycle. However with 2.4 systems wanting more power and the larger more powerfull servoes we have available to us now the Nicad may be limited in the larger Jets, brown out being the main concern. Power to weight ratio is impressive.