there are no best , just choose the 1 that suit u best . Rule of thumb, the higher the clock the more juice it should eat.
how to read his kernel name eg
TNP1536-512-STABLE65 = MAX CPU at 1536Mhz(u can go lower by using setcpu or similar apps)/ GPU at 512Mhz (fixed , can't lower)/ Stable release /based on version 65
TNP1786-307-ALPHA99 = MAX CPU 1786Mhz / GPU 307 Mhz/ ALPHA release (as the name suggest, its only an alpha)/ version99
Stock Gnex CPU MAX at 1.2Ghz and GPU set at 307Mhz
go for the stable release if you want proven and stable kernel
go for experimental release if you want to be living on the edge and test all the latest morfic put into the kernels
oh forgot this , if you noticed the kernel names either starts with TNP or TUV
TNP = Trinity Nexus Prime
TUV = Trinity Under Volt
So if you want to get a kernel with the lowest default power consumption, u can try TUV kernels BUT it may not work properly on your device as all device are different

Thats a great info..Thanks for it..appreciate that =) i guess i may go for stable TNP