Cant find my copy of Water, I think I may have lent it to someone....
Had at look at the link to KegLand, it bothers me that the blurb is long on hyperbole and very short on numbers.
You need to know the resolution (should be 0.01pH), the range the ATC works over (most meters wont work over 50oC)
There is a lot more info in the "Instruction Manual"
Its a bit of a worry when something says it measures to 0.01, but claims to be accurate to 0.05
I would urge you to read the manual very carefully before buying (anything)
Pay particular attention to the storage and use of calibration buffer solutions. Apparently "almost forever" is in fact 2-3 month if refrigerated.
I think its fair to say there are no good cheap pH meters, try looking for one that represents good value for money.
Mark