also understand, that the temperature compensation on the probes is only for the effects of temperature on the probe itself. it does not account for the change in pH that occurs in the wort itself - which is typically around .3
what i have for chilling samples quickly is one of the "slushy" drink cups meant to take juice or pop and turn it into a slushy for kids. I leave it in the freezer prior to brewing, then pull it out when i need to take a sample I add a couple ounces of wort to it and it chills it in under a minute.