Hi a1wish, you really do need to use Boss Bands for these workouts. You can always modify any workout, but many of the exercises in the workouts are just not feasible to do with TPE or latex stretch bands. This is especially true of the exercises that use a Boss Band. A Boss Band is really a continuous "loop", unlike a stretch band. Many of the exercises in Boss bands Total Body take advantage of the continuous loop design and would be difficult or even impossible to do with a non-loop stretch band.
There is probably less of a difference between Boss Loops and latex or TPE exercise loops, like our firewalker loops. The main difference is Boss Loops are mainly worn above the knees and Firewalker loops are mainly worn below the knees. You could probably modify this workout using a Firewalker loop, but I don't think you will find it enjoyable to do. Also, the workout would be totally different. It would be like trying to use a stationary exercise bike instead of a "spin" bike for one of our indoor cycling workouts. It's just not as effective or even close to being the same workout.
We also plan to use the Boss Bands and Boss Loops on Cathe Live and future DVD projects. Since fabric bands are pretty much unbreakable they will last for many years and as far as exercise equipment costs go, these bands are really a very inexpensive exercise equipment choice.