Ya they most definitely changed them not only did they change and upgrade they have a meter no one else has like the quick cal solution which is one of the reasons I went with them vs a blue lab or making my own w like a Adriano or something like it....
Ya u can have quick cal, storage and a cleaner solutions vs storage, cleaner,2 diff pH and 2 diff ppm sometimes 3 even goes w ph too even but all depends on the company....
When ur out in the field and having to calibrate each solution and throwing it out ea use very wasteful and time consuming vs 1 quick cal u stick the probe in the solution clear the old calibration setting and it will make a new one read 6.86 and 2500 tds @500 scale as it does 500 and 700 scale too FYI ...So put it to what your nute company uses is a good way to be insync w them as 500 vs 700 Is a huge diff most USA does 500 just not sure about there something to look up tho....
So I used to have a blue lab pH pen and it was a fuckn pos which is why I sold it and still have my trusty Hanna and it's one meter I can always count on and if it's off calibrate it and it's back to normal in a few..