As an inexpensive option for something akin to an onahole, they're portable, functional, and despite being labeled as "disposable" they can still be easily cleaned and re-used (at least until you've worn them out, which with frequent use can be sooner rather than later.)
As the saying goes, you get what you pay for. If you're going for re-usability, definitely give their spinner series a try, or look into their higher end options if you've a lot of disposable funds lying about.
