Don't bother with the hot springs at Banff. Little more than a warm swimming pool.
Disagree. After a day of hiking, horseback riding or exploring that "warm swimming pool" feels mighty good!
To each his own. For me it was disappointing. By their own admission they supplement the spring water with regular tap water.
Haven't been to Progresso but lots of people get dental work in Algodones and are very satisfied. I assume Progresso is the same. You're on the right track though, I would start with personal references.