So far not noticing any real advantages or disadvantages to the "curve".
I do not type on a flat service nor do I put the phone to my face (use an earpiece).
I found that my G3 Seidio holster works with the G4 (without a case) so haven't had to go through the whole "find a holster, case, etc. combo that I like".
I will probably get the leather back, tempered glass protector, camera lens protector and buy a quick circle case (pull the wireless charging parts and put them on the leather back)....and then I can call it a day.
In fact I really didn't notice the curve, my pointed it out while I had it sitting on the kitchen counter.
I guess I am too enamored with everything else....LOL