Liquid/Drops for Ph testing

Curious on your opinion here:
After lots of research, PH meters sound like they are very difficult and expensive to use/maintain/store for a hobby brewer.  And test strips appear to be widely opinioned as not accurate to be useful.  But what about liquid-based tests (such as pool kits and/or other ?liquid drop? tests for hydroponics).

I can?t believe I can?t find a thread on a homebrew forum about using liquid-based/drop methods of PH measurement for Homebrewing.  They seem to address all the problems of meters  (cost, accuracy, storage) for the intermittent user.

Specifically, something like link below seems like it would be quite useful to start to get an idea about your mashing PH?perhaps even nudging it to the desired PH.
https://www.amazon.com/General-Hydroponics-pH-Control-Kit/dp/B000BNKWZY

Am I missing something here?  Why isn?t everyone using liquid-drop based PH testing?

PS: there's probably some impact from temp when you try to sample your 155F mash....but I think the sample size is so small that chilled test drops may even mitigate this somewhat.  Sort of like putting "hot" drops on your refractometer; they cool almost immediately.)

A colorimetric test for pH is good when you have clear water to work with.  Once you add color bodies into the solution (like as in wort), the determination of end color becomes much more subjective.  pH strips are based upon this same indicator chemistry and given the low amount of liquid absorbed and the white reflective background are much more reliable.  Many brewers use test strips without issue.

pH meters are really not that difficult to work with and maintain.  Some basic understanding of how they work will help with the upkeep and protection of the meter.  Cheap pH meters can be had for around $10 to $20 from Amazon, but are not really reliable long term instruments.  I went through several over the years and as long as you view them as throw away items, they are not bad.  You do need to be wary of the accuracy of the readings as the number of digits they display does not always correlate with the accuracy they claim. 

Step up a bit and with some minor storage and maintenance and you have a more reliable set of pH meters to choose from.  I've worked with pH meters from $30 and up to several thousand dollars in my career and most do a suitable job as long as they are maintained.  Any pH meter, no matter the price, will not function if not cared for.

personally i use and recommend this

https://hannainst.com/hi98128-phep-ph-tester.html

for maintenance i use this

https://hannainst.com/calibration-bundle-for-beer-bottles.html

I keep a small amount of each calibration fluid, and storage fluid in a mason jar with a sealed lid.

hanna also offers many cheaper options for meters, from around $40 on up. I'll also warn you, I've seen many of their meters on homebrew supply store sites for 2X or more the price that they offer it directly. Hanna makes great quality testing devices and offers excellent support.

I would recommend getting a meter with a replaceable electrode though. just in case the first one i linked has replaceable electrodes and its waterproof