So far the transition has been pretty smooth. It does not seem like a large phone at all to me. I also have the M8 and the OnePlus seems to be the same size to me. It has a very nice feel in the hand. I do not use my phones one handed. It just doesn't feel right to me...i always hand hand holding while the other touches the phone or two handed while texting. But occasionally i am able to use it one handed. I am really enjoying this phone. It has become my daily driver over my M8.How was the transition to a 5.5" phone? Was it hard to get used to the larger screen? Are you able to use the ONe now comfortably and reach all the menus without too much hassle? Can you use it with hand at least occasionally?