I really enjoy using my MP6 II, the power options have never been a hinderance and I have the L mount adapter, but I prefer using usb c with the 4 or 8 battery adapter as backup, I just loop a right angle cable through the front post a couple times so it wont budge.
That said, recently I picked up a Zoom F3 and the sound quality to my ears is nearly identical to the MixPre. SD units tend to be smoother, but for a run and gun recorder, the f3 is great. I'd imagine other newer Zoom products operate similarly.