Unless you live somewhere where the water is so poor that they have to put so much chlorine in that it smells like a swimming pool, I wouldn't worry too much. Two of the longest-lived snakes had nothing but ordinary tap water their entire lives.
If chlorine is a major concern, I'd invest in an activeted carbon filter for your sink. Of all the filtration techniques, it will provide you and your snakes with the best quality water. If you use a reverse osmosis filter, you'll have to provide a mineral supplement.
Distilled water, on the other hand, should be avoided. Not only is it devoid of minerals, but it will also leech minerals, such as calcium, from your snake's body. Even with supplementation, your snake will be deficient, and would live a shorter life.
As for Reptisafe, it seemed okay until I read this claim on ZooMed's site:
<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font class="pn-sub">Quote:</font><HR></TD></TR><TR><TD><FONT class="pn-sub"><BLOCKQUOTE> Reduces pH (very important) </BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>
Drinking water should be slightly alkaline, not neutral or acidic. To compensate for the reduced pH in the water, minerals would leech from the snake's skeletal structure and bicarbonate would form in its blood. All things considered, I wouldn't use it.
[addsig]
