I just got rid of my SP for a helix
Wow....what a difference ...now I can actually make it out the door before the battery dies
The Thinkpad helix? I guess if you're talking about 10-hour with the keyboard dock, then of COURSE it should have better battery life. It weighs almost 4 lbs.
If you value battery life, smart consumers should figure out -- either you get a low-power device OR you sacrifice mobility (more weight) for more battery cells. This isn't rocket science.
That said, always buy what fits your requirements to get the most enjoyment. Yep.