The dial on my Ekos SE is .2 grams off, which makes it effectively useless. For the last few years I’ve been using one of those ultra-cheap OEM gauges, and have gotten good results. They can be a bit flaky, possibly because they’re sensitive to room temperature. I find it works better if you turn it on, put it on the platter, and leave it for a few minutes to settle. Even then, I need to take several measurements, just to be sure. It’s also essential that you use a calibration weight every time you use it, and adjust the reading accordingly.
A while back I got fed up with this flakiness, and searched around for something better than the el cheapo gauge that didn’t cost hundreds of dollars. I eventually bought a Riverstone model from the river (about $30), and it’s well worth the modest extra cost.
One other thing I’ve tried which seems to bring a small improvement on spring-loaded arms such as the Ekos. Instead of starting off with the dial at zero and positioning the counterweight to get the arm dead level, I just set the dial at the desired tracking force (1.75 grams for the Kandid), and use the counterweight to set the actual tracking force.
Conventional wisdom is that you should fine tune tracking force by ear, but it seems to one of those things I’m not very sensitive to. There have been times in the past where I’ve gone months with the tracking force one or two tenths of a gram off, and I never noticed anything amiss.
The tracking force that results from the dial setting always depends on the arm balance that was initially set with the dial at 0. Even if the arm seems “in balance” initially and even if the dial worked perfectly accurately, it is easy to be slightly higher or lower.
If in doubt, use a scale
Start from the recommended VTF by whatever scale is most repeatable then adjust it by ear to what you consider optimum, record the setting. Chances are the next cartridge won’t sound its best at exactly the same VTF anyway.