im using one now. and yes, i consider it too big to use one-handed without dropping it.

also, the physical buttons are way too easy to press. every time i hold it, i accidentally press something :(

5.5 inches is about the limit for me, with pretty avg hands, imo.

previous phones were sony xperia compacts. last one was xz2 compact and felt pretty good, though could have been a tad thinner/lighter.