Anybody have experience with these two 24-7 PH meters?

Yea thats the one i thought you were talking about. If you dip it in past the black part water gets in and fucks it up. Thats why i bought the water proof one. it is only 35 bux tho so if your a careful cheapo it might work out.

I had a Hanna just like that and it worked fine, I still have it and it's been 7 years retired it about 4 years ago and will buy a new probe and put it back to work. I also have a tri-meter and it works great. Blue labs has good stuff also.

http://www.betterthannature.com/catalog/product_info.php/products_id/4