Buy Stihl. Problem solved. It's not _quite_ as powerful as 24" gas-powered chainsaws, but it's really close for almost everybody.
You can also buy a battery pack backpack: https://www.youtube.com/watch?v=KQUhCXPkzsc (I haven't tried it).
You can also buy a battery pack backpack: https://www.youtube.com/watch?v=KQUhCXPkzsc (I haven't tried it).
Picking up and putting down a tool is a lot more work with a backpack and a cord. If you go around doing a ton of one kind of work (eg: weed whacking, blowing, sweeping) then it's fine. If you are pruning a tree and have to go between throwing branches and cutting them, it's annoying to manage the cord. Also, climbing hills with a heavy backpack isn't wonderful. Anywhere with slightly unsteady footing is made worse with a giant lithium ion battery strapped to your back.
As for the power/speed of cutting with the electric combi-polesaw... it's pretty great. I've had one for just over 5 years and the most maintenance I've had to do is replace chains and add bar oil. No carb tuning/cleaning. No worries about extended periods of inactivity. No two-stroke oil to mix into hard-to-find non-ethanol gasoline.
Overall, I love the thing but don't get the idea that it's a 1:1 replacement.
I'm not a chainsaw guy myself, but it was quite nice to use when I've borrowed it.