I'm on the fence between the AX53 or the Panasonic WXF991 or 981 (without EVF).
I do want 4K (have 80"4K Sony TV) but don't shoot a lot videos, I'm more of a photography guy (D810 and gold ring lenses ). I'm pretty much getting this for my wife who always tell me to take a video while shooting with my dSLR. Which i hate, lol.
I had Panasonic SD600 which was a great camcorder (recording recitals, kids games) until my daughter dropped it in the ocean. The camcorder will be mostly used for recording family vacations, recitals, performances, kids games (basketball, soccer). If I want to shoot more professional looking video, I could always use my D810 on tripod using better lenses and lighting.
AX53 pros for me are the optical stablization (BOSS), cons: might too big for my wife compared to the old Panasonic SD600.
Panasonic 981, pros smaller form factor, cons: image stabilization maybe not as good as Sony.
One other thing that bugs me is that smartphone video quality is getting better and for the price of about $1K for a camcorder I wonder if it's worth it. I actually tried using a DJI Osmo Mobile with my S7 Edge / Note 5, and the video looks awesome, good enough for day to day family video/memory capture specially in a good light. But the set-up is not as convenient as a camcorder and the ability to zoom beats out a smartphone camera.
Getting a G7 or G85 or other mirrorless 4K is pretty much out, as my wife won't want to deal with DSLRish form factor for video. She didn't like the DJI Osmo mobile set-up either, so I'm back to camcorders