Not by a long shot. Yes there have been tremendous advances in electrode technology but these allow a stable reading in a $100 meter (vs. $200 for a stable electrode but a few years ago) but not in an $11 meter.
Don't be silly (we'll go ahead if you really want to - it just makes you look foolish). Once the electrode is under control (rms stability of 0.01 or 0.02 for, say, a couple of hours) it is the buffers that determine the ultimate accuracy of a pH reading. With a two point calibration at 4 and 7 accuracy of a bit less than 0.02 is possible at mash pH. Yes, there are reasons why one wants better accuracy than is possible (or I should say probable as I have never handled one of these pieces of junk ) and I explained in #4 why a serious brewer needs all the accuracy he can get. Perhaps you should read that.
If you can't land between 5 and 6 without a pH meter then I don't think much of your skills as a brewer. Even the worst pH prediction spreadsheet will do better than that and they are free. Why throw away $11 on something your instincts and experience should tell you is likely to be garbage? If they can transport it here from China, pay Amazon's markup and sell it for $11 what do you think it costs them to make it? Do you really think it is possible to make a decent meter for $5 even with very cheap Asian labor? Accuracy isn't the only issue here by any means. The thing will probably fail after a couple of months. Think about other products you have obtained from China in this price range.
Me too but it's funny how the guys that understand the process and pay attention to the technical details tend to be the ones that produce the best beers. There are exceptions, of course.
Well I usually stick to the Brew Science forum where the readers tend to be more sophisticated WRT to things like pH measurement and when I post to one of the other fora (such as this one) I sometimes forget that. To make good beer requires pretty tight control of pH and if you are making good beer you are controlling pH either implicitly or explicitly. I post things like these criticisms because I hate to see people waste their hard earned money. If a guy can't afford a $100 meter then he can't afford to throw away $11 on a thing that will probably turn into a piece of yellow plastic in a couple of months either. Better, IMO, that he should hang on to the $11, forego 20 pints (@ $5 ea) at his local, make up for that by brewing an extra 20 pints at home and buy one of the meters with which people on HBT have had good stability performance.
No offence, but from what you have written it sounds like you have never used a pH meter before. The "cheap" pH meters in my lower level chem labs varied by a few tenths each reading and they are much better meters than the one you linked to and that's with calibrating them immediately before using them. One way I compensated for this in lab was by taking multiple readings and averaging them. For upper level chem labs like analytical chemistry these meters were useless. For accurate pH measurement I had to use a pH meter with a good electrode and also monitor the temperature.
In all honesty I wouldn't trust an $11 pH meter to get you within a few tenths of the pH reliably. The solutions you need to calibrate and store a pH meter are going to cost more than the meter itself. Why not follow everyone's advice and save the $11 and put it towards a good pH meter? I mean why did you even come here and ask advice in the first place if you weren't going to listen?
Best of luck
How will you do that with a meter with rms accuracy of 0.1? You won't know with confidence whether your pH measurement of 5.5 represents 5.4, 5.5 or 5.6 or even, really 5.3 or 5.7. An 0.3 or even 0.2 change in pH (from 5.7 to 5.5, for example) is enough to make a profound difference in the quality of the beer produced - enough to turn on or off those 'bright flavors'.
It's not incumbent on me to prove anything to anyone. I'll offer what I (and others) know and if you are too foolish to accept what you are told by those more knowledgeable than you its to your detriment and no concern to me.
You made an $11 mistake which could have been avoided had you looked before you leapt rather than afterwards. It's not a big deal. We've all made mistakes of that magnitude and greater. Keep the thing and see what it will do for you or, more likely, teach you about $11 Chinese knock-offs.
That isn't likely given the mind set you have demonstrated here.
Yes. Absolutely. Beers mashed at 5.7 are dull/flat in flavor compared to ones mashed at 5.5.
How can you be so sure I haven't tested them against lab meters?
I wouldn't do that to my fellow brewers. The goal here is to set the record straight.
