We were using Wika level probes for almost a decade and now we hope to use some economy products. As we found similar designs named Holykell with ideal price here in Malaysia, we purchased some samples from them, BTW, Holykell is a Chinese factory. The samples' testing is OK and we are considering to purchase hundreds of units.
Just before the decision making of purchasing from them, we hope to get more information about the differences between Wika level probe and Holykell level probe.
For a potential future purchase of hundreds I'd think you'd run own evaluation installing a one of each side by side in the same tank and determine the installation, setup, operational and performance differences for yourself, and do a test on one a tank considered "problematic".
If you really expect someone else to have gone through an evaluation it would help to know which technology/model devices you're talking about.