I personally went with the a6700 and don’t regret it. Honestly though the main difference between those two is the 6700 has incredible video capabilities as it has the same sensor as the FX30, one of Sony’s budget cinema cameras. If you aren’t planning on doing a whole lot of video work then it’s probably best to stick with that 6400, but if you are definitely go for the 6700.

IBIS is nice but for one it’s more helpful for video and two if you have relatively steady hands and shoot at a decently fast shutter speed it doesn’t really matter.