I wouldn't say so. I have multiple LiPo's.So you can squeeze more mah into the same cavity as a conventional Li ion?
In my 4 year old BDC stabwood is a 3S Turnigy 1500. Basically 3@18650 each with 1500 mAh.
Also a Turnigy 3S 1300 mAh, 3x1300 (3900mAh) that is the same size and shape as 2@18650 (swappable in my LV efusion Duo)
A fullmax 3S 900mAH (2700 total) same size as a 21700
And finally a 4S 1000mAh (4000 total) capable of 400 watts, barely bigger than my Mirage
The main benefit would be much lower voltage sag when firing.