In th beginning and towards the middle of when we were playing KOF XIII you'll see neomaxess more often. But as everyone starts doing HD combos more consistently or long DC combos, you'll start seeing less neomaxes. In a match up if you're unable to create HD combo opportunities or long DC combos, you'll use neomax. If you can, you'll end up doing more damage in HD combos.
Power gauges charge up at a much faster rate than drive bar, so when you use a neomax, you'll have to think twice whether it's worth it or not.
And for Iori's neomax, it may seem like 0 frame in that vid, but believe me, there's a very small start up window. This is through experimentation of using it many many times as I've been using Iori since day 1. It's still damn good, but just pointing out it's not godly like Vice's.