Thanks for the quick responses. I had my own reservations about the gel leaking out, especially with the sudden and extreme temperature differences. Was just curious if anyone had used them successfully. I think I'll stay away from the weird frozen gel.
I have seen those Rapi-Kool contraptions in my LHBS, just never really paid them much mind. Now I have seen the light, and I think I will give it a go. My only concern is being able to effectively stir with that monster in my kettle
Thanks again, cheers!