I am in the minority here..
I have been using a traditional dechlorinator that contains sodium thiosulphate (Hagen Aqua Plus) for the last 15 years or so and have never made the switch.
I don't really need the nitrite/ammonia neutralizing capabilities of Prime because all my tanks have been cycled and established for years. It has been years since I last had a nitrite or ammonia spike..
Prime is cheap because it is very concentrated, but the Aquaplus is pretty concentrated too.
the turn off for me is that Prime is about twice the cost of the stuff I am using now for the same amount...
I buy a 2 litre bottle of the dechlor, and it costs 29.99 canadian.
the same size bottle of Prime is 69.99 canadian.
Now, it probably treats more, but I cant justify switching when what I am using has been working so well for so long.
count me in the minority who does not use Prime.
and besides, Prime smells bad so I hear.