It does have a slight whine when charging, but that's to be expected from the switched mode PS that it uses.

Keep in mind that the batteries did get pretty warm while charging.

It has a high pitched whine noise to it when charging, it gets louder the more batteries you have charging

It does have a brite blue light when plugged in & charging, but not a problem as I have it in the corner of the dining room & it's seldom seen

I like that I can charge many cells at once, but as others have mentioned it does make a small whining noise while charging

I can't rely on the technical features of the charger to properly charge or even indicate proper charging.

True that some batteries Are displaying 'error' when charging or just displays an outline of a battery, & I know the battery's good

With this charger, I always have freshly charged batteries handy when needed.

This product gets very HOT when charging batteries

Inconsistent and incomplete charging.

So far works well , fast charge, LCDs indicate charging status.

The first charge on my Tenergy 2500 mAh premium batteries went fine.

I hesitated to buy this because I used to charge my AAs at 200 thinking it was "easier" on them, but some research revealed that charging TOO slowly might actually lower the effectiveness or decrease the battery's lifetime.

I did discover they don't get nearly as hot when charging 6 AA's and 6 AAA's.

Can't figure out how to 'refresh' charge works.

Seems to put a proper charge on the batteries

Bottom line: this thing works as advertised, charges each battery independently, and keeps each cell on a trickle charge compatible with the requirements of NiMH batteries (no trivial accomplishment.

Super helpful when you are charging old-timers with new batts.

Easy to use, works well charges quick.

one of the things i REALLY like is how EACH battery is charged independently.

I like how each slot charges independently from the others and that you can see if it's done charging or still charging.

Like, if you leave this in a room charging some batteries and go outside at night, people will walk by and wonder why you have a blue room

I was looking for a new battery charger to see if I could get a better charge on some of my older batteries that were no longer taking a good charge from my old charger

love charging or refreshing 12 cells at once

500 seems to be the generally accepted optimal charge rate for AA.If you need to refresh batteries, manually select charge rate, or do anything more complex than auto-charging, I'd suggest one of the 4-bay LaCrosse chargers.

I have learned through experience that fast charging kills batteries

It does emit a high pitched noise while charging but it's not a big deal

Works perfectly as advertised and charges quickly

Been happy with the batteries of this brand and this charger works as it should

Works exactly as it is intended to