Really cheap one ... (http://www.aliexpress.com/item/Mini-Pocket-Pen-Type-PH-Digital-Tester-for-Homebrewing/32394425930.html)
What do you think guys? Is it worth anything?
I've been using them for a couple of years and I think they're fine for checking ballpark pH samples.
i use one of them, no major issues with it. be aware that it can be 0.2 off.
If thats a bit much then look for one of the ones with +/- 0.02 they would be about twice the price.
In that case will go for THAT ONE (http://www.aliexpress.com/item/Compact-size-ATC-6020-PH-meter-with-auto-calibration-for-3-points-calibration-and-LCD-display/32335618881.html)