I have STS & 2 of the Fit Tower dvds & don't have a tower. The first time with STS I did both the squat rack & Plyo leg option in Meso 3 ... I used a barbell and a weighted vest for the squat rack option. I used bands for pull-downs & chin-ups - Cathe has crew demonstrating these options. The 2nd time with STS I purchased squat racks (from Valor fitness) and stretched a padded bodybar across them for pull-ups & chin-ups - works fine for me as I'm not strong enough for full chin-ups/pull-ups. I use the squat racks with a step-bench to rest the barbell for chest work too - just as Cathe uses her tower. It can also work as a barre for Fit Tower dvds, but so can a chair or railing or a wall. And you can do the band options for chin-ups/pullups, or a chin-up bar if you have one.
It depends on how much weight you can safely lift over your head as to whether you "need" a squat rack or tower for squats. But a weighted vest is helpful (I did try putting dumbells and plates in a backpack as an option - didn't care for it- moved & slipped around too much).
Maybe some more Cathletes can chime in as to what they use ....
