I have a meter from the same manufacturer that is nearly identical. It worked OK for three or four years, now I can't get it calibrated across the range I need. You have to calibrate pH meters using solutions of known pH, before you use the meter to test soil pH. Our tap water, municipal water supply, has a known pH of 7.6, & I use 5% white vinegar for the low end of the range, pH = 3.5. I have switched over to dye indicator solutions for pH testing, because they are inexpensive, reliable, and there is no calibration step. Bromocresol green indicator is yellow at pH = 3.8, and blue at pH = 5.4. That's a fairly narrow range, so I also use bromothymol blue(7.6 to 6.0) and bromocresol purple(6.8 to 5.2). However, I was able to get good results with the Hanna Instrument pH meter, so I know they work OK.

I Think that Grainger stuff is more than enough.
They have already said its accuracy is +/-0.2
The instrument works on a simple electro-chemical principle, measuring the current as in a battery cell.
The results you will get will depend on your sampling method. Too much water, too dry a sample, fine soil, chunky soil, ?? can give you different readings.

Most garden veggies can thrive in a wide PH range.
The median is 6.8 . This means that from 5.8 to 7.4 is fine for better than 90% of what you grow.

On the other hand, if the Ph is low or high , you cannot change it overnight and in a big jump.