I had a small bottle of betta plus when I purchased my 0.5 gal hospital tank. The NutraFin Betta Plus, correct? I'm not sure if it has salt in it, but it does have IAL in it (also the chemical itself is a little brownish so they're ...possibly...not lying about IAL).
I used it to treat my QT because my large bottle of Prime would be too much of a pain to get a 0.5Gal dose-worth. My fishies are okay...no health problems, no side effects, no mental degradation.......haha.
SeaChem Prime is popular for a reason, because a lot of urban areas now use Chloramine to treat tap water. Regular dechlorinators only get rid of the chlorine part, but now you've got the other half...ammonia floating around now.
Source of all knowledge, XD: http://www.bettafish.com/showthread.php?t=66595