I use the method of bottles with frozen water to chill wort along with an ice bath. Is it more sanitary? Absoultely not. Wort chiller is actually next on my purchase list, but I have never had a batch that was chilled this way get infected. I sanitize them b4 freezing, and place them in the freezer the day before or at the very beginning of brew day. This seems to make it less likely for infection to set in, but I'm just guessing. Has always worked for me though.