Is 64 bit processing really worth the CPU hit

What if I use a mix of Cubase plugins + VST2 plugins? Would be still worth going 64 bit?

Also, I have a bunch of Waves plugins (CLA-76, CLA-2A, REDD, ADT, TG12345). If those plugins are Vst3, why they are not listed as plugins that support 64 bit processing?